While I've never watched my little ponies... I can at least respect a grown adult watching cartoons. Avatar: The Last Air Bender is hillarious, and I didn't start watching that until a few months back. Rocco and Spongebob are right up there with Beavis and Butthead and Frisky Dingo for me.
One time we were at a pool party, and a buddy and I were inside watching cartoons while the food cooked and the kids swam. This lady walks in and says, "Oh my god... you're grown bellybutton men watching cartoons?!" like there was something wrong with it, so I told her to shutup and called her a Dumb C-Word, and everyone laughed.
The power of laughter is an amazing thing.
That being said, if I want to feel secure in my mascuilinity I'll get baked and watch Sailor Moon.