My XS Max is 2 yrs old now and 96% battery health. I charge nightly overnight on a generic Qi charging pad, plugged into a slow-ish Anker (definitely not an 18w+ one). During the day when it hits 80-85% I usually charge here on the couch back to 100% (wfh these days) otherwise in the office I have another generic wireless charging stand.
I usually get a new phone every other year, and occasionally upgrade every year (8 Plus to X to XS Max).
I've always heard the slower the better for charging and between 50% to 80% - which I do for my Tesla battery but not for my phone. I generally keep the phone mostly topped off, albeit slow charging. If I was keeping the phone more than 2-3 years, I'd still probably just get a battery replacement at the 3rd year if the degradation was more than 85%.