32GB on a Z370 with an 8700K works fine.

Yes. No issues.

That specific motherboard and CPU support DDR4 RAM up to much higher capacities (usually 64GB or 128GB depending on the board). 32GB is well within spec, and you won’t run into any compatibility problems if you use matched sticks in the correct slots.

Memory controllers on those chips handle 32GB without breaking a sweat. Just make sure you’re using a 2x16GB kit (or two 2x8GB sets matching in speed and timings) and that your BIOS is up to date. If you’re gaming or doing heavy multitasking, it’s a good upgrade.

You won’t see a performance gain going from 16GB to 32GB if you’re only gaming, but for video editing, VMs, or running multiple Chrome tabs like a madman, it’s useful.

Don’t overthink it. The spec sheet says it works, and it does.