Chiming in to add an anecdotal data point in support of the parent's comment. I too own a System76 laptop which is running their drivers and PopOS (Debian and Ubuntu derivative). Sleep/wake works well.
My personal ThinkPad E495 has pretty much flawless driver support.
Granted, I'm running different distros (Ubuntu on the Dell, Solus on the ThinkPad) but the fact that the Dell Precision is certified specifically for Ubuntu is pretty disappointing.