In some niche cases, you'll notice some improvements when gaming with Wayland, but games that render through Xorg may have small graphical issues. Some overlay applications (like WTRTI, which provides an overlay for War Thunder, for example) may not work at all, as it's an XWayland window trying to talk to another XWayland window, which can be very difficult. Your mileage may vary, and you may be just as pleased with some results as you would be disappointed in others.