I've got an S20+, and I'm pretty disappointed with the battery life so far. To the point where I'm concerned it's faulty.
It seems to be using around 10% an hour when I'm walking around (with the normal use). This is with the screen on 1080 / 60hz.
It's just finished its learning phase, so I'm going to give it a full recharge, and see what I get. If it's still the same, then I'll try and get it replaced.
The other thing I've noticed is that it won't charge with my normal multi-charger (Satechi), unless I switch it completely off! Wireless charging works fine, and it also works with the supplied Super Fast charger, so it must be an issue with the charger. However, it worked fine with my S10+.