If you don't take more than a few hours to get used to a completely different browser, editor, desktop/mobile OS, etc., you probably just didn't use all its features. I know that I still had Firefox reflexes after I had been using Chrome for a few weeks (this was a few years ago when Mozilla made some poor decisions, I tried voting with my feet).
There's a long sliding scale from "knows how to use most features of the new software" to "uses every single feature maximally and never, ever presses the wrong hotkey because an old muscle memory happened to fire". I don't think the latter is a reasonable bar to set for "get used to the new software".
Then again maybe I'm being unfair here because if I'm really honest about it, the reason I didn't switch over to Chrome was that you couldn't start an in-page text search by hitting the / key like I was used to doing in Firefox. (I've since found many other reasons to keep using Firefox but at one stage that was the sticking point...)
