Not just Wayland.
Every experience I’ve had so far with running anything Linux on Nvidia hardware has been unpredictable to say the least. Not just personal experience but those around me as well. Somehow it always comes down to driver compatibility issues, and there is a reason Torvalds used such strong words when describing the developer experience in dealing with Nvidia.
And these problems will likely persist until they decide to fully publish the source for their drivers.
Slugs to be you then, I guess. :P
In all seriousness, the graph shows different species as fraction of total uses recorded. Since the paper is mostly about mice, and behavioural differences under different circumstances, it being unfair to the slugs is probably not such a big deal here.