[edflsafoiewq]

I think this is the same as the brush stabilizer in Krita.

[baxuz]

Possibly in tldraw as well, but that one was also velocity based

[kilpikaarna]

LazyMouse in Zbrush was the first one I think? But yeah, this feature is not uncommon.

There's even a program called Lazy Nezumi that adds global mouse smoothing, rulers etc. to Windows.

[RicoElectrico]

And Affinity tools.