While yes, you may think "at level 19 you got auto-shot and a pet, it doesn't really change" it actually does. Between traps (the most dynamic form of CC, which you get at 20), 21-point talents (scatter shot or intimidation add a lot), and farther on down the road you get some tools to make life more interesting.
Honestly, anything is going to be "auto-attacking my way into next week" to some extent if you're just grinding. On a rogue, 55% of your damage in raids is white damage. On a paladin, you'll just auto-attack with a seal+judge every 8 seconds. On a warrior, you auto-attack and wait for rage. Hell, try raiding on a frost mage. Can we say "Frostbolt frostbolt frostbolt frostbolt frostbolt frostbolt frostbolt frostbolt frostbolt frostbolt...." While it's not auto attack, spamming 2 on your keyboard isn't really twitchy.
However, you get fun fights where you overaggro, or tricky raid bosses, or you can do PvP to make the game more fun. I know I've used (within the same fight) multiple traps, mend pet, all my shots (including conc shot and scatter shot), 3 different stings, scare beast, feign death, and several melee abilities as well just because I kept aggroing mobs 5+ levels above me. Was a fun fight.
Oh yeah, try kiting as well. Go at level 20 and take on a level 28 elite, that's always a blast.