I really think taking publishers to task for rebooting older characters as more diverse, newer characters is misguided and a little naive.
The perception is that the market doesn't support new characters, and evidence seems to bear that out. So the best way to diversify a cast, like it or not, is to tag a new character with an old name.
When this is the reaction to attempts at diversifying, I suppose the publishers would be better off to just ignore the reactions and follow their instincts. Ride out the complaints and work to establish the characters in their new identities so that people forget Miles Morales wasn't always Ultimate Spidey.