If you want someone to blame for the failure of Thomas Cook, you can point the finger at me. I did it.

I didn’t single-handedly sink one of the world’s oldest and greatest travel brands. But it was me, and millions like me, who were once Thomas Cook customers, who abandoned the famous name years ago.

There were lots of reasons why Thomas Cook went to the wall on Monday leaving 600,000 Europeans to wonder how they were getting home. The dropping value of the British pound, weak consumer confidence in the face of Brexit, high fuel prices and, of course, a small matter of needing a cash injection of nearly $2 billion.

But one of the key reasons was that many holiday-makers are now content to make their own holidays. For millions, the days of needing a travel agent to book an all-inclusive package are over — we’ve unpackaged the package holiday.

Twenty years ago, 50 million people globally went on holiday. Last year 1.4 billion did — yet each year package holidays make up a smaller and smaller proportion of that number, particularly in advanced economies.

In 2018, just one in seven Brits who went overseas used a travel agent to book their trip.

The last time I used a travel agent was two years ago to look into airfares to Korea. They were no help, I’d found a cheaper a deal online.

“Thomas Cook is a globally iconic name, probably one of the most famous names in travel and to have company as iconic as them going under is a really big shock,” University of Technology Sydney tourism lecturer Dr David Beirman told news.com.au.

“But for a lot of people now, their idea of planning a holiday is to book flights online with a carrier and book accommodation with Expedia or other online companies.”

Back in the pre-internet package holiday heyday of the 1980s and ‘90s, companies like Thomas Cook could lie back on their corporate sun-bed, relax, and watch the money roll in as Europeans escaped to the sun.

It was Mr Thomas Cook, after all, who in 1841 invented the concept of the package holiday. His first trip was a rail tour between the cities of the English midlands. By 1855, he was taking tour groups to marvel at the sights of Europe.

A century and a few decades later, I would turn up at London’s Gatwick Airport with my family (Heathrow was reserved for fancy business people) ready for our two weeks in the Spanish sun.

Companies with evocative names like Horizon, Going Places and Wings, would promise you sun, sand and sangria. All those names vanished long before Thomas Cook succumbed.

Aeroplanes owned by the holiday companies themselves would ship tourists en masse to Mediterranean airports. Invariably, they would land after midnight but still the heat of the warm Southern European air was a pleasant shock.

In arrivals, a company rep would be hold aloft a sign with your hotel name on. You would then be shuffled onto a minibus to your resort, stopping at many others en route.

The next morning, bleary eyed, you’d have a meeting with your rep by the pool with a welcome drink included. They’d cheerily tell you about the kids club, the hypnotist or comedian who would wow you in the hotel ballroom that night and a fascinating tour you might like to partake in, for a few pesetas more of course.

Then, when your fortnight of buffet breakfasting and sunbathing was done, a minibus would ship you back to the airport for the red-eye return to a chilly Britain.

The memories are happy, but when I booked my first holiday I didn’t take Thomas Cook but low-cost carrier Ryanair to Amsterdam and a bed and breakfast booked online. I didn’t need the all-inclusive frills.

I’ve been to plenty of beaches, but it has never occurred to me since to book a package holiday in order to go to a beachside resort. I just book all the elements independently.

As for travel agents, I used to book airline tickets through them, but it’s just less hassle — and just as cheap — online.

“The old days when travel agents sold airfares aren’t here anymore because airlines aren’t paying the commissions they used to,” Dr Beirman said.

“If any travel agent tried to do that now they be out of business.”

He said package holidays were still popular for certain demographics, but the concept was victim to an intergenerational pincer movement.

“Family travellers still want certainty and security; if you look at all the Aussies that go to Fiji they will tend to book a package tour with a respected airline.

“But younger people and the grey nomads now have a greater tendency to be independent travellers.”

The waning demand for package holidays by Britons was the backdrop for Thomas Cook’s demise. However, Dr Beirman said it had massive structural flaws elsewhere.

“That they had 600,000 stranded people suggested that side of the business was doing OK,” he said.

It was Thomas Cook’s vertically integrated business model and debt that crippled it. It operated from 600 shops which came with 600 rents and 22,000 staff to pay. It also transported passengers on Thomas Cook planes and even owned some of the resorts the passengers arrived at.

“That’s all well and good if all those elements work really well but where Thomas Cook came a cropper was that certain parts were not working well, particularly its airline business,” Dr Beirman said.

The debt that weighed down the firm stemmed from an ill-advised merger in 2007; this was compounded by it actually owning few assets beyond the goodwill associated with its brand; and that British travellers were waiting until the last minute to book holidays due to heatwaves at home.

That it collapsed in the northern autumn was not unexpected. Package holiday firms are generally flush with cash in spring as people buy their holiday for the coming summer. It’s after summer when that seam of fresh cash dries up and travel firms have to pay their bills.

Australian travel agents still have lots of shops, but crucially they don’t own airlines. Instead, they buy seats on the likes of Qantas, Virgin Australia and Fiji Airlines and often at a steeply discounted rate.

Dr Beirman said travels agents had shifted from a one-size fits all model to more specialised choices.

Some travellers might want “modular” holidays where they add individual elements, a flight and a couple of tours maybe, but leave the rest flexible. They may book their own Airbnb for example.

At the other end of the market, travel agents also offer more complex products.

“If you want to do a 10 country tour, that’s something that doesn’t lend itself to booking on the internet and the market for that kind of travel is significant,” Dr Beirman said.

If they do this well, the likes of Flight Centre and HelloWorld, Australia’s biggest travel agents, are less liable to be buffeted by the crosswinds that weakened Thomas Cook.

The UK Government will now scrutinise why, like an exhausted tourist after two weeks in Torremolinos, Thomas Cook fell in heap. But a huge reason is that when people like me started doing holidays differently, the company found by Mr Cook in the 19th century didn’t come along for the journey.