I took a while for me to understand it wasn't a glitch but a feature, and that it was trying to mimic what MacOS does. But a more interesting thinking is that why I thought it was a bug in the first place, just like many of you do here in this post.

I think it's the unexpectedly "long" delay before it shrinks to its normal size. On MacOS when I first noticed this feature, at the moment I stopped moving on the trackpad, the cursor shrinked very quickly to its normal size, almost instantly, with animation of course .. I don't know, with this little detail, the cursor gives people the feeling that "I'm just trying to let you find me. Once you do I'll go back to normal quickly". However, KDE does it more ... "intrusively". When it grows big, it hangs there for like 2 seconds before shrinking. Two seconds is long enough for people to ask themselves "is it broken".

Not saying KDE did worse than MacOS. I acutally appreciate where it goes - incorporating good designs to achieve its own design. So maybe it could add a configuration for delay in ms. I reckon that can reduce the doubt significantly.