@sangzeel: I also keep my consoles, but many people sell them because (1) they need money for a new system or games, (2) they don't have the physical space in their homes, (3) they don't have enough TV inputs and don't want to mess with cabling.
There are many valid reasons for needing/wanting BC on the XBox One X.
@nintendians: Got my X360 at the beginning of its lifecycle. Had all my other consoles plugged in too, and none of them suffered any ill effects. I think this was down to poor manufacutre, poor airflow (even though I didn't stick it in a cabinet) and bad luck.
@nintendians: This does happen sometimes. I went through FOUR X360's (RROD) before getting one that worked properly. Didn't even play that much (2-3 hours per week).
@Random_Matt: Getting the fastest makes no difference with game boot times on the Nintendo Switch. Save some $$$ and get an additional game instead! (...or a screen protector, or a case, or a stand, or a controller...).
@silversix_: How many portable consoles are out there that use hard drives? Portable hard drives would be noisy, drain battery, and break down frequently. They are not meant for life on the road - SSD or flash memory (like microSD) is the best choice for a system that will get moved and bumped around a lot.
These are the same reasons why Switch does not use optical media.
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