.com is owned by a single company(and other top level domains owned by other companies), why shouldn't more companies own other top level domains?
The fact single companies manage TLDs doesn't factor into my thought process on how we should manage the TLD namespace.
It sounds like your problem is really with Verisign et al., perhaps the fight you're looking for is how individual gTLDs are managed in the first place, not assuming that part of the model is fixed and exploding the namespace in some bizarro business fairness.