It's a popularity contest and those bands aren't terribly popular. It's no knock on them, just the nature of the beast.
and that's the problem. It's like having a Movie Directors Hall of Fame and excluding Fellini because of his poor box office. Or keeping out the Coens for the same reason.
Sure, sales matter to some degree. I'm not arguing for the Minutemen or Mission of Burma despite both being hugely influential and totally awesome. But if we're just going on sales, put in Huey Lewis and Linkin Park. Linkin Park sold a diamond record, too. There has to be some level of merit, and it's also not like the Replacements are some massively obscure band. Almost all of their albums charted and they ended up on a major label by their career's end. Same with Sonic Youth and the Pixies, who are two of the most influential bands of the 80s. Though I do notice you cut off my paragraph to ignore the part about Velvet Underground.
The question is: what is the purpose of the museum? Is it there just so the music industry can honor their best salesmen? Then plunk in whoever has the best sales figures and no one cares. It's not supposed to be a museum to things that were popular 30 years ago (which is what it has largely become).
My point is if the point of the museum is to tell the history of rock n roll, you should induct the bands that are most important to the story. I like Heart. I think Dreamboat Annie kicks ass, but you can certainly tell the story of rock n roll without them. On the flip side, I think you can;t tell the story without mentioning prog (so in comes Yes and probably King Crimson, even though I agree with Jan Wenner on prog).
But if I'm telling the story of 80s rock, the story is largely this: the big labels pushed bland hair metal acts who sold sex, drugs, and escapism as well as "classic rock" acts which sold Boomer nostalgia. And as the new generation came of age, they largely rejected these bands and turned to hip hop, MTV Euro-style pop, metal, and what would become "alternative". The 90s alt-rock boom and the explosion of gangsta rap were built on the bedrocks of the 80s.
So, if I was building a museum dedicated to the history of rock, I'd include bands from each strand, even the dead end of hair metal. The 80s bands I'd likely include would be:
Van Halen (already in)
Metallica (already in)
Public Enemy (already in)
Run DMC (in)
And Michael Jackson is his own category.
I think you could go down ballot in some categories (Duran Duran and INXS for MTV-style pop, the Pixies and Fugazi for indie, NWA and Eric B & Rakim for hip hop, Judas Priest and Megadeth for metal, Motley Crue for hiar metal). But the key shouldn't be "what's my favorite band?" or "who sold the most records?" It should be: "which bands are essential to the story?"