All of these bands with the exception of Dokken were at the tail end of the hairband era, at a time where the scene had become tremendously derivative. Everyone was sounding the same and the quality of bands being signed was getting less interesting or compelling. Once the Seattle bands made some headway and the tide had turned, the labels followed suit and these bands (and scores of others) were set adrift. Grunge didn’t destroy their careers, the fickle nature of the pop market did. let’s be clear here, all that we are talking about was the pop market for hard rock and metal. The fans of that music, to begin with, didn’t desert them. They did, however, need to operate with less of a marketing presence. Some bands adapted well to this, others didn’t.
Since I am a huge 80s Metalhead I can honestly say that they do get much respect for all they have accomplished. Those three bands you mentioned (Motley Crue, Ratt, and Dokken) were sort of the “pioneers” of the Glam era, not to say that there weren’t others. As far as respect, notoriety would be a more appropriate word, especially when talking about Motley Crue. What I think happened is they were a bit overshadowed by the likes of Poison, Warrant, etc…but you have to remember that respect is earned, even when it comes to bands. For instance, if a band has done some “not so nice” things to fans in the past, then they might not receive as much respect. Doesn’t mean they still aren’t liked, just not a lot of respect. Does that make sense?