Curious - what phone do you have now?
Edit: Just say in a post you have the 13 pro? Assume it's not the 13 PM. Pretty sure before 16 I had issues with typing Ill not being corrected to I'll. I've noticed some of what you typed as well. Being in IT too, I recognize the flaw but consider it low enough of a priority to just move on.
It is the 13 Pro non Max. Like I say, I’ve always noticed autocorrect being bad but just turned it off. However I was still using autocomplete, just manually selecting it. That’s what has gone so haywire in 16. I have to manually type just about everything now because autocomplete only suggests wacky things. I type enough on my phone that it’s a big problem for me.
And that’s the weird thing. On 15 and prior I never noticed this being a big deal, especially the contractions. It’s like on 16 it had every English contraction removed from its autocomplete dictionary. I’ve never seen it in release notes, but someone on these forums said autocorrect was improved. So I don’t know if they actually changed anything or not, but it’s worse for me to the point that I have now gone in and added lots of new stuff to the text replacement custom dictionary that I never had to before.