That's great & obviously the best solution for some!

However, the gist here seems to be that for
some non-casual gamers, rather than buy an expensive, high-end Mac for both serious work & more demanding gaming, if you can get your serious work done on a lower-specced Mac, maybe far better to get that, then buy (or build) a gaming PC. With PCs being upgradable & then also needing to use your Mac's hardware much less (note, I'm talking about non-casual gamers), it probably works out cheaper in the long run
I tend to agree with that view, be it based on my personal experience. My iMac's logic board fried after 2 years 10 months (not guaranteed as I expected an expensive desktop to last longer). Yes, my fault for not buying the guarantee.
That I was doing a lot of gaming on my iMac is probably besides the point, & maybe I was just unlucky with it going when it did, but I'd never make that mistake again. I now accept that for most of my serious needs a lower-end Mac is fine (I prefer OS X to W7), but PCs are better for gaming.