Well for analysis reasons I cracked open my 4e books. D&D 4e was the first tabletop RPG I ever played, but I have no nostalgia for it. After reading some discussions online, I refreshed my memory of the books.
And...I get it. Its not my thing, and if you dislike what it is, its elements become pure flaws, but I generally get what its idea is, and what the people who like it see in it.
Its not a MMO. While it has designated combat roles, its combat isn't MMO like, and it is not nearly as restrictive as a MMO. Its still very videogamey, but Its more a CRPG. In videogame terms, oldschool D&D is more a Rougelike (akin to streets of rogue or unexplored), while this is a CRPG (akin to Shadowrun Returns). And I can sorta see why some people that actually like D&D basic see it as more a direct successor.
The combat sub-game of D&D is more disconnected then ever within it, and thats where the most amount of character option based sacrifices happen. In addition the powers make no fucking goddam sense at all from the perspective of relating to the 'real world'. The character roles are boiled down to specific combat sub-groups for the sole purpose of making the combat sub-game fun (for the people that like this sort of thing). There is no 'Sniper' role, or 'Illusionist'. But striker and controller. Which is making huge player option sacrifices for the purposes of making generally everybody at the same level during most scenarious, in combat or out of combat. There are 'magic' options for stuff, but its almost always costly. Creating a temporary illusionary guy will cost you a few hundred gold.
To the people that are OK with it, they see the D&D combat sub-game as having always been largely disconnected from the 'real world', with the way hit points work only tangentially relating to the characters themselves. To them, they are more happy leaving anything outside of the specific sub-game elements to the GMs hands, and if a combat encounter is to happen, then have it be as mechanically engaging as possible. Its generally way more GM facing then something like 5e.
Now this isn't my thing, but years later I get it. And I respect it (though not the marketting campaign and presentation of materials). And I may play it over 5e if that ever becomes a choice for me.