A little bit thicker (even if you use layers) and you'll definitely get there.
While I understand, entirely, why mouse pointer movement is to be avoided at all costs for a screen reader user, that doesn't mean that either a mouse or mousepad cannot be effectively used if the mouse movement can be prevented. With a mousepad, that means covering the thumb trackpad area with something thick enough that it won't recognize touch. With a regular mouse, virtually all of which are optical these days, a piece of tape over the opening where the laser is emitted to detect mouse movement on its resting surface does the trick.
In both cases the mouse buttons remain available for use for their native purposes. And given my experiences with mouse emulation over the years, and that's up through recently, I'll take the treated mousepad/mouse every single time. It eliminates a ton of headaches.
Brian - Windows 10 Pro, 64-Bit, Version 20H2, Build 19042
The depths of denial one can be pushed to by outside forces of disapproval can make you not even recognize yourself to yourself.
~ Brian Vogel