For me, I decided it depends on your battery use. If you are having issues running low on battery don't give it a 2nd thought and just charge to 100% and save the worry. If, like me you found that, when charging to 100%, you always had 40 or 50% battery left at the end of the day, then go ahead and set it to 85%. I did that and when I am home on wifi I still find I can have 40% left at the end of the day. Even when out most of the day and in areas sometimes searching for service, I still never get below 20%. But for those that have their screens on for hours and hours or use it for games, etc. 85% may not work and I would say just go ahead and fully charge and use your phone.
When I buy one of these new phones, I am usually in sticker shock for a while so think I will be keeping the phone for at least 4 or 5 years. But once I get to about 2 years of ownership, that thought is long gone. I kept my Pixel 2XL for 4+ years, but that was more because of not finding a phone that I really wanted to replace it. I finally just bit the bullet and got the S22. Sure, it's not perfect, and later this year or next Samsung or some other will put out a phone that will make me think I should have waited longer, but that is a never-ending cycle. If I found I needed the 100% charge, I would not hesitate.