Hopefully it doesn’t come to that and cases drop enough that governments are happy to remove mask mandates.Personal opinion only: I think masks go away by the end of summer. Why? Because I think people will simply stop wearing them. I'm not making a judgment on whether that's right or wrong. But when we have hundreds of millions of doses of vaccine out there, people are just going to say, "I'm going back to normal," whether governmental authorities want them to or not.
The only issue is private businesses will still have the right to require masks if they choose. I’m not sure how a place like WDW would react, but right now they are going beyond what’s mandated by the government. I suppose if enough people avoid businesses that still require masks that capitalism could take over and force a change. Once Disney has had a chance to vaccinate their staff it seems much less likely they keep masks around.