I have serious concerns with ventilation and how skins/case affect cooling. Too many skin/cover makers play fast and loose with Apples's placement of cooling vents. Because air intake location and type vary with sub-models, some cases and skins sold as covering multiple models may block a critical air path in some Macs. That can be lethal to a computer.
Apple's images of the 2021 14- and 16-inch MBPs clear show intake vents on the lower section of the side at the junction between the bottom plate and the chassis:
The other critical area in all MacBook Pros is the hinge. It is the exhaust point for hot air on all MBPs and the air intake on some 13-inch models.
NOTHING must occlude or restrain any of these vents. If you opt to use a cover, find out if the seller and/or manufacturer will guarantee replacement of your computer should the skign causes damage. If not, walk away.