Was iOS 16 good or bad highly depends on what we are talking about.
Speaking of the features, iOS 16 was great. I really like new Lock Screen customisation options (Although, I'm not a huge fan of doing any customisations on my phone, I like to use devices as they are); Live Activities are quite useful with apps like Bolt, Uber; Battery percentage was a small but extremely needed for so many years feature; Freeform has given me useful ways to study easier, create some sort of mind maps and collaborate with others.
If we are talking about problems with iOS 16, I would say, that this version is too buggy. Of course, I mean battery life (it had been poor for me till iOS 16.5), buggy notifications, I am also experiencing some sort of lags and freezings across the system. And these are just a few of the most popular examples, more have been discussed on the forum.