Adjustable scrolling speed is useful (I mean, I haven't used it, but I can see why one might want it). Creating a GUI to adjust it is an uninteresting polishing task.
Swaywm has the ability to set this (you have to edit the config file). It seems weird that gnome or whatever you use lacks this option. Although, gnome has a lot of t's to cross and i's to dot, maybe they just haven't gotten around to it.