It would certainly fall into that category now, but I refer back to one of my previous posts where I point to the black screens (now known as running out of memory) happening for people on the default A320, CJ4, 747 often after longer flights just as they reach a destination and the scenery loaded in. That was August 2021 just after MSFS released on the platform. There was a huge long thread about it at the time, that went on for over a year or more.
Here’s that thread (note the date, August 2021, default aircraft & not many extras available at that point in time on xbox, I know as I was using it at the time.)-
Devs have tried tweaking memory over the course of sim updates, but then as you say more complex airliners and more dense airport scenery came along. The Xbox (especially the series S just doesn’t have the RAM to handle it all.