Difficulty: Yes
Progression: No
Finally we have a game that sticks to the D&D rules (mostly). Last one was NWN2 17 years ago. I think we deserve a D&D game every two decades, don't you? 5e isn't about building a character, it's about playing a character. I think it's an amazing improvement to 3.5e (4 doesn't exist, as we all know). If you want complex character building, there's a lot of games and rulesets for it. 5e isn't that, and I'm so so so thankful they did a (mostly) faithful implementation.
Games like pathfinder are so complex that a lot of people just give up creating a character or they fall off the game midway because they just can't be arsed. The completion rate of such games is quite low. This is a much better game for not having complex character building.
Personally, I don't think that fewer choices can be a better thing because a lot of people can't be arsed to choose. I understand that this doesn't apply to everyone, but at least in my case, more choices translate to more engagement and replayability. Besides, you only level up 12 times within a ~130h playthrough - I don't think it's an absurd concept for someone to spend more than one minute to make progression choices. Would it be that cumbersome?
D&D can be about both building and playing a character. It's not like 5e hasn't made any good changes, but it seems to have trimmed the fat a little too much in my opinion. As for the having to complete it and move on to the next one argument - personally again, I am enjoying it and in absolutely no hurry to complete it (and I don't understand why that should be the case with this or any game), especially since, as you said, we barely got any proper D&D games in the last two decades.