Sure, but you can see how "this power just works" without any lines of interaction or engagement can have issues. And it's not like we're done with such abilities- a Wolf Totem Barbarian in 5e grants advantage to his allies when they attack something adjacent to him. How? Why? Weird Angry Totem Magic, I guess.
Barbarians are pretty supernatural. After depending on totem they can sprout wings at a higher level. But even without that I can see how having a raving maniac in my face could be a bit distracting. That or that the barbarian could have specific techniques to keep enemies off balance.
If Come and Get It or Rain of Steel were written as spells in another edition, a lot of people would go "huh, cool" and accept that they work. Magic doesn't always need to offer saves, checks, or attack rolls to do it's thing. But historically, non-magic does, and the issue with the Martial Power Source is that people assumed it was "non-magic, just badassery manifest". So these powers are jarring if the Martial Power source is magic, and if it is, then that means the Fighter is now a magician, which, pick any thread, lol, you'll find a lot of people who don't want a "magic Fighter".
I'm not saying they should have designed these powers differently. A big problem for 4e was that many people expected it to be the same old D&D and were confused by the fact it was now more like Earthdawn or Exalted.
I'm not sure I'd say confused, more just that I wasn't playing a game with the same thematic components and feel as previous editions. Just to repeat, just because it wasn't the game for me doesn't mean that it wasn't a decent game for others. After the ton of errata from the first printing, anyway.