My wife's MB Pro faced an upcoming support reckoning with Apple, and I just tossed Linux on it. Problem solved ;)

I've also used FreeBSD on (non-Apple) laptops in the past. It actually worked ok, I even had wireless working (this is very hardware dependent though, and things may have gotten worse over the years for all I know).

Based on the rest of your profile I think you might enjoy switching that workstation away from OS X to FreeBSD. Of course, it means some tinkering and looking for new tools to replace the ones you use now, but the tinkering is half the fun... :)

I like to get that kind of use out of my machines though I upgrade workstation on a more regular basis (though the last one went a full 7 years with nothing new but a RAM upgrade and an SSD midlife) - You come to identify with the hardware after a while, it takes on a life of it's own.

Since I'm (excluding Win10 for gaming when I rarely have time) exclusively a Linux user I get to use the old hardware for other purposes at the end until it finally becomes either useless or lets out the magic smoke (as my 2004 R50e Thinkpad finally did - man I miss those keyboards, so much better than the T470P (which itself is excellent)).

It paid of just recently, I had 2012 Vostro 3750 kicking around and when schools went into lockdown with a quick wipe and Fedora install it made a perfectly serviceable machine for my step-son to do his remote learning on - there was an irony in running MS Teams on Linux on a machine that wouldn't have been able to run current generation Windows 10 and Teams anywhere near as comfortably.

My last personal desktop was about 11 years old when I retired it. It had an AMD Phenom II 965, just to emphasize it's age.

It started life with Windows 7 (Win7 was like a month old at the time) and was subsequently upgraded to Windows 8, then Windows 8.1, then finally Windows 10 (and all it's "feature" updates) until it was retired. It ran slower than a new system, but fit my needs perfectly.

If Microsoft had arbitrarily decided I wasn't allowed to run Windows 10 on that hardware, it's very likely I would have installed Linux or BSD - after all, the hardware was a non-trivial investment and discarding it purely to please some company really rubs me the wrong way.

So, I guess I can sort of understand why people jump through these hoops... although personally I would just move onto some other OS that doesn't undermine my ability to operate my personal computer.

It probably helps that it sounds like you mostly use it as a dumb terminal. If you had a compute-intensive workload, it would make sense to upgrade, since even a quite powerful 12-year-old desktop is likely outperformed by a current-model smartphone for many types of work.