I bought a 360 a few months after launch. Went through the red ring deal twice (both covered under warranty luckily), and 3rd one is still my daily driver 15+ years later. As far as normal retail releases purchased when the console was current, I've definitely bought more 360 games than any of my other consoles.

I wasn't really digging the Xbox One but got one as a gift a few years after it released. What little interest I had in it was mostly due to it being backwards compatible with the majority of my 360 games, and it having the same online ecosystem (same friends list, achievements, etc). My Xbox One library isn't nearly the size of my 360 and mostly consists of deeply discounted digital games. I can count the physical discs I own on one hand. Several years later I can say I, definitely glad I ended up getting into the system and there are quite a few really good games that I love and would have missed out on if I only stuck with the 360.

I picked up a Series X once they became available to a casual buyer, maybe a year after launch. It being totally backwards compatible was pretty much the main selling point as there were 0 Series X exclusives I was interested in. Really the only reason I got it was it seemed to be the definitive way to play my existing library (faster load times, upgraded visuals and FPS boost on many games).

Fast forward a couple of years and I own a grand total of 3 games that are exclusively on Series X and not on Xbox One. 2 of those 3 were available on PS4. I won't be purchasing the next Xbox because there is no way I'm painting myself into a corner again, missing out on a lot Japanese developed games just for the sake of keeping the same online ecosystem I've had for 15 years. If I never bought another game for the rest of my days I'd still not be able to finish the ones I own right now, so there's no pressing need for me to drop nearly a grand on another system when I've barely scratched the surface of what I already have.