If it was by TS, the achievement would be 1000x worse. Right now, anyone who wants it can get it. TS? Maybe 300 - the rest wouldn't be able to because they're level-locked. Cheating would be MUCH more prominent. Look at Chromehounds, if you ever played it. It wasn't a huge title, but it had leaderboard-based achievements - and the leaderboards became a joke. A not so popular game (less popular than Halo Wars), and the top 1000 players were all boosters. A game with the Halo population base? lol...
The achievement is hard to get, yes. It take a large amount of dedication to get, but who said achievements shouldn't take a large amount of dedication? And as far as grinding, there are many immensely popular grind-fest games *cough*WoW*cough*. Some people like that type of thing and do, indeed, think it's fun. It gives them something to strive for and a sense of accomplishment when they finally achieve it. If you don't like that, then just don't get it. Nobody's going to shoot you if you don't. Just because you don't find something fun doesn't mean someone else won't. And again, I stress the fact that it's a SINGLE achievement.
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