I seem to recall reading of TMP being denounced at conventions - by the actors themselves! If DeForrest Kelley's "This
is Star Trek I" [RE: Wrath of Khan] had happened in this era, sites like Trekweb would be glorifying it ("Kelley rejects TMP!") just the same as they did that 100-fan poll at the 15,000+ attended Las Vegas convention which voted Into Darkness the worst Trek movie.
IMO the fandom hasn't changed at all, merely the form of communication.