Well, RFA rules do protect the team for a time, what we did used to see when RFA status was around but the cap was not were shorter term deals that ultimately led to poor teams having to sell off key players to rich teams as there was no question they were losing the UFA years. The Oilers, in the span of 14 years, lost Gretzky, Coffee, Kurri, Messier, Weight and Guerin to this inevitable reality.
With the hard cap, revenue sharing and the cap floor - any team in the league, even the lowly Coyotes, must be able to afford their key players (like, say, OEL) because they need to spend a certain amount of money as a rule and other teams can't artificially raise contract prices to a point where a player like that might ask for 12M instead of 8.5M.
As has been explained already, parity doesn't spread championships around. Parity creates a semi-equal base for teams to land on and creates bizarre surges and drop offs like the Colorado Avalanche of the last two years. It does not and can not create an environment where there are more Sidney Crosby's in the league for teams to compete with Sidney Crosby.
This is the Oilers biggest advantage moving forward. No matter where else we don't succeed, other teams will not have a Connor McDavid to compete with Connor McDavid.