Can you put a hot pan on a quartz countertop?

No, and this is the one place quartz is clearly weaker. The resin that binds the quartz begins to soften and discolour at around 150 degrees Celsius, so a pan straight off the burner can leave a white or yellowed patch that will not polish out and is not covered by most warranties. Granite came out of the ground hot and does not care. If you cook the way that makes this likely, either choose granite or keep a trivet within reach of the hob.