I disagree. 3rd edition was using Traveler tactics from the 1970s in character creation (i.e., you could DIE, or end up with a character so handicapped as to be unplayable, and the spectrum wasn't just on that end... you could end up with wildly successful characters right out of the gate, completely out of balance with the other player characters). AToW doesn't suffer from that. The skill specialization system was also unwieldy in play. To drive anything with a mixed armament (AC/Energy/Missile) required three different gunnery skills. It was better in some ways than 2nd Edition, in that it gave you much more well rounded characters. AToW achieves that with a simpler skill system and organic integration with the table top game.
Personally, I think AToW is the best RPG system BattleTech has seen so far, and Destiny is in no way poised to replace it. Given the reaction to other incarnations of the Cue system, it sounds like there's plenty of scope to be worse.
And to be clear, every time I've said AToW isn't that hard, I've offered to help people work through their difficulties, not said "they shouldn't be playing the game".