No issue here. It was off before, on purpose, and still off now.
Edit: I was referring to my 16 Pro. I also have an XS that I keep updated, and the setting to off-load unused apps was enabled. I’m certain I looked at it sometime in the past and it was off, which is my preference, but can’t say when or how it came to be enabled. Both devices are on the 18.3.1.