I am not sure that is fair; the websites above mention that they can no longer purchase laptops without a Microsoft license, which hurts their ability to remain profitable.
Ie at one point you could argue that if you didn't like AT&T, then the market would create a viable alternative. It never did, and was broken up as we know the free market does not solve everything.
In this situation, you could argue the market would create a viable alternative, but Microsoft has a consistent track record of influencing the market monopolistically.
It's just the market that has gone in this direction.
As mentioned previously, it used to be the case that you could make a living off of making custom PCs and selling them for a premium. You can still actually do this, charging for a 15% premium or something like that, and make a part time job out of it. But then you have to provide services such as overclocking and water-cooling. Back in the days of XP and Vista, all you had to do was assemble a system from OEM parts and sell it. You could offer higher quality parts + a Windows OS + better performance/price ratio and still be profitable because the system you made would still be cheaper than a pre-built computer.
The thing that has changed is, as I said, the market. You can't do that anymore because the margins are prohibitively small. You need to buy in bulk and sell in bulk to make any kind of money.
But that's not an issue with Microsoft or this secure boot thing, that's just the way that prices have changed in the market. A lot of companies can no longer afford to sell systems without the extra money from MS sales and the bloatware. It was never all that profitable to sell Linux machines to begin with, and it's even harder now. But it's still possible. It's just that you have to sell huge numbers of them, more than before, in order to stay afloat.
Another thing that you have to take into account is that it's a niche market to begin with. Most people who enjoy Linux also know how to manage it, know how to assemble a computer, and would prefer to set up the software/hardware themselves rather than have a company do it for them.
I could be wrong in some of what I have above but that's my understanding of this whole issue.
Unfortunately, none of the websites says why suppliers X, Y and Z, who used to sell them laptops without Windows, will no longer supply them with laptops without Windows, if that is the case. (There's no evidence that it is.)
Also, none of the websites says why they can't just buy their laptops directly from Chinese white box PC suppliers. Am I supposed to believe it's cheaper to buy them via another European company that actually buys them from a Chinese white box supplier? Really?
Microsoft's record of trying to influence the market dates from around 1992-95, and it spent the 2000's under close judicial control, so your fact-free monopoly assertion doesn't carry a lot of weight now.
Either way, Apple has conclusively demonstrated that the market certainly will support a viable alternative -- and one that commands huge profit margins. This doesn't mean suppliers of crappy low-spec/high-priced Linux laptops are entitled top a free lunch, or that politicians should interfere with the market to prop up their failing businesses.
Ie at one point you could argue that if you didn't like AT&T, then the market would create a viable alternative. It never did, and was broken up as we know the free market does not solve everything.
In this situation, you could argue the market would create a viable alternative, but Microsoft has a consistent track record of influencing the market monopolistically.