Right, because we all begin good and not at lesser skill levels. 
Let me dumb it down so you don't misunderstand again.
Having more scrubs means eventually more good players will arise. (We all begin as scrubs when we first play a game we don't know, it doesn't mean just because your a scrub you doomed to be a scrub forever.
Having more good players means more people taking the game seriously and finding their own styles/strategies.
Simple enough?
You know, a certain level of skill transfers between fighting games. Like, basic fundamentals and adaptability. I'm not sure how many particularly good players you know personally, but the ones that I know are able to pick up a new game very quickly. They are generally pretty strong in a new game right from the start because their basics are strong and they learn fast. Likewise, there are players that don't get much better over time, and suck at all the fighting games they play. I know plenty of those types too, we call them scrubs.
It's true that not everyone is awesome on day one, and we learn over time.. but no you don't want "more scrubs" because by definition a scrub isn't likely to improve. However, you do want "more players and hopefully some of them are good". But more than that, you want people to actually like the game and want to get better at it.
Just getting a bunch of people together doesn't necessarily mean people will keep playing either, look how many games use to be at Evo and SBO and are now dead and gone. They had a community and they failed to keep it. And if all these players being brought in by netplay are actually scrubs then a lot of them will probably drop off pretty quickly in favor of another game.
Anyway, it's incorrect to think that netplay will automatically bring in an influx of people. There's actually several PC fighting games with netplay that have zero community. There's also a ton of old games that have netplay support through emulators and have zero community either. Netplay doesn't automatically make people want to play a game.
With a PS2 release there's at least a small chance at a tournament scene. With a PC release all you'll ever get out of it is online casuals and the occasional side event. The latter would only be technically a good thing if the game was going to die anyway, because then at least some scattered fans can have fun flogging a dead horse. But without a console port it isn't likely to be taken seriously on a large scale because the majority of gamers have equipment for and play on console, not PC.
