Should I enable XMP for my RAM?

Yes, enable XMP (or DOCP on AMD) — that’s what it’s for. Without it, your RAM runs at a conservative speed like 2133 or 2400 MHz instead of the 3200 or 3600 MHz you paid for. Usually nothing goes wrong, but if you get instability, back off to a lower speed. Not enabling leaves performance on the table in games and memory-sensitive tasks.