The answer to this post

https://www.dell.com/community/XPS/XPS-15-9510-optimal-TB4-docking-station/m-p/7987537#M87189

seems to answer my question, but I'm considering getting the Caldigit Element Hub (Thunderbolt 4) to use with my (being built) XPS 17 9710. The hub will supply up to 60 watts of charging, and of course the power supply that comes with the laptop supplies 130 watts. The post cited above seems to imply there's no problem leaving both the hub and the power supply connected, which I would suspect anyway, but I'd like to be a little more confident.