I've played a few fighters in my life, I like to fight. Smash is the one I've put the most time into. There was a time I had interest in competing, but that's over now, possibly forever.
In games, most PvE content can reasonably be expected to be beaten by most people, even the "hard" stuff like Dark Souls or whatever. You can't expect that with PvP though. It's inherently not designed for everyone to be successful at (that's just the nature of competition really), and a skilled/smart human opponent is well above what the AI can do for the most part. And really, people are not cut out to be good at everything. It's not like an RPG where you can get strong enough by mindlessly grinding enough. Even if you do put in the investment and not mindlessly, there's no guarantee it'll ever work out.
I still like to maintain enough skill to consistently beat the highest level CPUs, but that's it really.