[lgieron]

That is only true for constructed (I've known people who made a living out of playing 8-4 drafts on mtgo). And even for constructed, it is only pay to win up to a point where everyone has access to all the cards (by either buying or borrowing), which is where most competitive constructed players are.

[pyrale]

Last I checked, pro gaming was always a mix of constructed and draft/sealed, which meant you couldn't reach top level without practicing both extensively.

A full edition set costing in the thousands, and there being 3-4 sets per year, the price to compete is fairly high.

[lgieron]

If you don't aspire to be a pro player and just want to have fun, you can compete in limited only. I have friends who do that. I myself chose phantom sealed deck tournaments on mtgo, which, provided you don't suck, are basically free.