I will add that 4e worked very well for D&D Encounters and Living Forgotten Realms. Man, I miss LFR.
Oh, yeah. For playing with strangers and as a pick up game, 4e would be the go to edition. So few issues with interpretations, nearly zero balance issues (especially compared to previous editions), everyone plays using more or less the same framework for their characters, meaning that it's really easy to teach. As an onramp for D&D, 4e is a really good one.
It's just a terrible edition for established groups who didn't play using the assumptions of organized play. I've often thought that the fact that I played online, using Maptools at the time, meant that moving to 4e was a breeze. Maptools had a 4e ruleset already baked in - all you had to do was add in the specifics of your powers. Because everything was standardized, playing 4e on VTT was fantastic.
But, again, that's so much down to my experience. I couldn't imagine trying to play 4e face to face with only pencil and paper and no battlemap. Yikes. How in the world would you track the ten thousand little fiddly bits? We actually made a sort of sub-game to see how many effects we could stack on a single target at the same time. I think we hit twelve or thirteen at one point. On VTT? No problem. In person? No thanks. This is one area where 5e is greatly improved over 4e.
On a side note though, I keep seeing people claim that 4e would be a great video game. Umm, first off, there's 5e right there which has one of the most popular video games for D&D ever, so, it's not like 4e is alone in being translated to video game form. But, the other thing is, I have no idea how you would actually do 4e mechanics in video game form. There are so many interrupts and out right do-overs in 4e. Unless it was turn based, there's just no way to translate 4e into a video game. 3e works so much better as a video game, as does 5e simply because you don't have so many mechanics which allow players to chain interrupts together.