From what I remember, the main criticism of the d20 systems was that it was too flexible, and that the game ended up very build-oriented. Some of the design decisions behind 4th edition were an attempt to streamline it with lessons from online RPGs, but part of the reasoning behind it was that this streamlining would move the focus away from the character sheets a bit - by not writing everything down in rules, things would be more up to DM interpretations.

I cannot say to which degree the game systems actually helped in practice; I switched groups between editions, and my 4th edition group was 90% improv theatre people. That there would be more roleplaying was pretty inevitable.

I also haven't played 5th edition so I don't know the changes there.