I just picked Mech Arena to give it a try and help out a friend who was sponsored and can already tell I won't be playing long? Why?

Because the game won't let me, or rather Plarium won't.

I have no idea why you're still using the the archaic energy system, nearly every gatcha game these days has ether dropped or never had it. Not only does it make f2p players lose out further on gear but also play time. I'd probably drop a few bucks here and there to upgrade my favorite mech's/pilots but what's the point if I can't actually play the game? 

You drop the stupid energy system and more people will not only play, but play, and pay, more.