This is a failure of the Linux Foundation to push back on proprietary hardware vendors, one blaring example is Nvidia. Even Linus has commened on Nvidia.
The Foundation should stop allowing proprietary hardware in Linux, instead these vendors donate $ to the Foundation and we are stuck using this hardware.
Another example is Secure Boot, some laptop manufactures are no longer allowing Legacy Boot. Were is the Foundation on this issue. Instead Microsoft donates large amounts and nothing is said about who signs the keys. It is just about impossible for many people to install Linux (or a BSD) on some new hardware without jumping through Secure Boot Loops.
And we have Intel ME, totally closed, the Foundation did nothing to complain and open that up either.
I could go on all day, and I am sure others can bring up many of these issues I know little about.
I think you're wrong on this one. You seem to be mixing up UEFI vs Secure Boot. The elimination of legacy boot in favor of UEFI has nothing to do with Secure Boot being enabled. Secure Boot is a good thing. In this case Microsoft is just acting as a Certificate Authority. Mainstream distros like RHEL, Ubuntu, and Debian have signed bootloaders. They pay MS a modest fee for what is essentially CA services. If a hobbyist distro doesn't want to pay then they don't get the benefits. A lot of OSS developers don't even sign their code because they object to paying for a code signing cert. If you want to play in the walled garden you have to pay the toll. Despite this I've yet to come across a device that prohibits disabling Secure Boot.
I know if I need to get a new Laptop, I will need to either pay twice the average for an open system that meets my needs, or spend months looking for compatible hardware.
So far the ~8 years old Laptop I have is working fine with Linux.
The one people have been predicting for decades because they refuse to understand how Linux works and/or they want attention.
None of this is new. None of this is even hugely interesting. Red Hat is one distromaker out of many, and nothing makes anyone use them or their products. Trying to conflate one distro with Linux as a whole is common among people who are either ignorant or attempting to troll.
I just can't see it being taken over by anyone, Valve or anybody else.