It isn't because noone complains that it doesn't bother anyone

.
I don't really mind, it just makes you sound like a child all worked up. Maybe you should try all caps next time?
I rarely get OS for the changeling, but that's usually because I don't think of it, and I should (I usually just get them for detection).
But you know what? The changeling is awesome, and
you aren't losing anything by using that spell.
Here's an example: I make overlords for control, not as scouts. But they're actually decent scouts! So sometimes I'll use them to scout!
Well the OS can scout like an OL, but it's an even better scout because it's got the changeling, and you don't risk losing your control when you scout with a changeling.
A bunch of units come with added functionalities that aren't core to the unit, but are actually a good boost in certain circumstances.