Twilight-Kun
Pokemon World Champion
Are we just going to ignore the Rescue Lusamine Arc?The difference is that Rowlet has battled a reasonable number of opponents that put a real fight. As in he had to endure damage back and put up impressive manoeuvres. He hasn't bulked up much, but that just shows even more because he can be competent and clever with what he has and not need to get magically bulked up the moment things get too even handed.
Steenee's beat up Meowth a couple odd times. In one instance she could only do that because he was held down by Instruct, and in the other two she needed a DEM evolution. Sure she holds a record for never fainting or even suffering a return hit, but she's never really been in a position she risked doing such.
I mean, I don't blame you, but come on...