In an environment were people are playing to win, Pokemon are used only because they are good. A Pokemon having high usage does imply that it's good because of this.
without usage stats, 'high usage' implies nothing. i'm just WAITING on people to drop statistics on this thread to prove me wrong but so far it hasn't happened.
Except that Lopunny runs Fake Out itself and is naturally faster than Mega Kangaskhan even in it's base form (not to mention most of the rest of the format after mega evolving) and that Lopunny is played almost exclusively as an all-out attacker, making Taunting it a waste of a turn? I really think that Lopunny is being downplayed here in a big way: It's flawless coverage, access to a strong Fake Out that cannot be blocked by Ghosts, ridiculous speed stat and unparalleled versatility with it's last moveslot makes it a physical attacker to be feared. While it's certainly no wallbreaker, it's high BP moves make up for it's weakness relative to Kangaskhan, and it puts in so much work against frail and fast attackers (like Greninja and Gardevoir).
i think you need to be reminded that HJK takes off half of your health EVERY TIME YOU TARGET A PROTECT. i also think you need to be reminded that literally everything can at any point use protect. "but lucariojr, you can just predict around protect and use HJK!" is an argument that's only relevant if you can read minds. prediction goes both ways and i would much rather use something that doesn't bite me in the ass when i get outsmarted on something as common as attacking into protect. the next best thing is return which can't score any SE hits even if it can get a few more neutral hits, then low kick which varies in usability and only caps out at 120 (same as close combat) against a select few pokemon. if you've ever played garchomp, you know that it has a hard time scoring OHKOes with a ~135 base attack with a jolly nature and without a boosting item. mega lopunny is in the same boat, but it has 1. worse defenses to cover itself when it misses out on a KO 2. an unreliable STAB option that undermines its already poor defenses which happens to be its main weapon 3. it requires some form of outside chip damage or helping hand to grab OHKOes on even (physically) frail pokemon like gardevoir. example:
252 Atk Mega Lopunny Return vs. 4 HP / 0 Def Gardevoir: 127-151 (88.1 - 104.8%) -- 31.3% chance to OHKO - garde can just run a teeny tiny bit more defense to avoid any possible OHKO
252 Atk Mega Lopunny Return vs. 4 HP / 0 Def Greninja: 124-147 (83.7 - 99.3%) -- guaranteed 2HKO - when has greninja been relevant, exactly?
and these are the pokemon you said it "puts so much work against". even with ice punch:
-1 252 Atk Mega Lopunny Ice Punch vs. 0 HP / 0 Def Landorus-T: 132-156 (80.4 - 95.1%) -- guaranteed 2HKO
...you're not doing anything impressive.
ok, so at this point if you can accept that lopunny isn't very strong and has an unreliable option that would be needed for it to be considered strong, let's look at lopunny's other qualities: a fake out that can't be blocked by ghosts, its speed, and what it can do with a third slot. first off, kangaskhan (a much better mega) can fake out ghosts already, so that's nothing new (and honestly, not amazingly useful). its speed is good, but guess what else has speed? answer: everything when paired with speed control from stuff like thundurus's twave, cresselia's icy wind/trick room, and of course talonflame. we're in a meta that has access to speed control; having absurd speed means a lot less nowadays. ok, so now what can it do with that third slot? notably, you have ice punch (covered before), a second fighting move (which might be a decent pick, actually), and encore. encore synergizes most with HJK and fake out, so it's probably the best option. but even then, we have raichu, which acts as better team support with lightningrod. also with encore, fake out and HJK, you're strapped for moveslots and have to choose between return and any hope of survivability with protect.
in conclusion: mega lopunny sucks.
Mega-Altaria needs a lot of team support. But if you get it, she counters Mence pretty well, and some of her common teammates counter her checks hard.
altaria doesn't counter mega mence because its main attacking type is flying. physical altaria has a harder time with it, and i'm not entirely sure if hyper voice can ohko it. it does naturally do a lot to it though as a fairy type.
what would your idea of teammates be? what checks would they counter?