This is the right decision.

The deal is that the Patent and Trademark Office has always rejected trademark registrations that offended it's delicate sensibilities. This included matters such as obscene names; they wouldn't let you trademark "JHE's Fucksticks," for example. Then it expanded to things that might be offensive. The case at bar related to a band formed by some Asian guys that wanted to trademark their band name, "The Slants." Now none of that is possible as it amounts to the government preferring some speech over other speech, which is a big bad 1st Amendment no-no.

This doesn't allow The Redskins to keep their name. It allows them to trademark their name under the federal system of registered trademarks. They probably had some other protections under the common law and maybe even state law. And they could have kept their name even without trademark protection. This gives The Slants and the Redskins a significant protection, but it is only a trademark protection.

This won't stop the NFL from continuing to press the Redskins to change the name, or, perhaps even to force a change. That is a private matter, and the 1st Amendment only regulates government conduct.