Wikipedia is and has always been a wiki; reverting bad or controversial edits has always been expected from day one.
Also Wikipedia has developed an editorial line of its own, so it's normal that edits that go against the line will be put in question; if that happens to you, you're expected to collaborate in the talk pages to express your intent for the changes, and possibly get recommendations on how to tweak it so that it sticks.
It also happens that most of contributions by first timers are indistinguishable from vandalism or spam; those are so obvious that an automated bot is able to recognize them and revert them without human supervision, with a very high success rate.
However if those first contributions are genuinely useful to the encyclopedia, such as adding high quality references for an unverified claim, correcting typos, or removing obvious vandalism that slipped through the cracks, it's much more likely that the edits will stay; go ahead and try that experiment and tell us how it went.
There are plenty of "bad and controversial edits" on Wikipedia, just some are more acceptable than others. Wikipedia is an oligarchy.
> reverting bad or controversial edits has always been expected from day one.
How charming of you to think that the well-meaning contributor is going to happily smile and agree with you when you tell them that their well-meaning contributions are bad.