The point is, he made statements in the past and you want us to ignore them, but that rule only applies to Trump, and not Rush.
There was a time when Rubio was believed to be more conservative than he has turned out to be. People learned a lot about him though he actions. My opinion has certainly degraded a great deal over time. Can Rush have the same situation? I guess not.
Heck, even Mark Levin had great words for Rubio, interviewed and supported him as a Tea Party candidate. As his deceit has become common knowledge, Levin has eviscerated him.