"Predictive" replaces text automatically, even when autocorrect is turned off ... how do I prevent that? [on iPhone]

Not sure you can stop it if you don’t want to turn predictive off and don’t want to add text replacements (although not relevant to true typos). How to use Auto-Correction and predictive text on your iPhone, iPad, or iPod touch - Apple Support

The alternative (although it may be something that feels tedious until it becomes habit) would be to click on what you are typing (if it is what you want it to be) when you see the predictive text appear (while it is still the lighter grey color) so that the predictive text isn’t what applies. If you hit the space bar the predictive will apply

Yeah it took a little while for me to get used to but I do find it helpful when it predicts the phrase I am about to type so I can just hit the space bar for it to apply and get the text done faster. Like I said though….you can manually override it by clicking on what you are trying to type before hitting the space bar which indicates you want the predicted text shown (I guess it could be seen as a backwards way though because I think many would prefer it to show the predictive text like it does and if you want to use it then you get to click on it instead of hitting the space bar which many of us hit without much thought indicating you want that predicted text). I guess if they get enough feedback complaints they may eventually consider changing it but that’s a huge unknown

I noticed exactly the same after updating to iOS 17. So for now I will also keep it turned off as it is now really inconvenient and would force me to type the same word multiple times.