With regards to gatekeeping and fandoms in generally, it's really easy for fans of music to profess a "love" for [insert band name here] because they really like one or more hit singles. Really, their language should convey they love [insert band name here]'s hit singles, rather than the band, because saying that to a seasoned or diehard fan gives the impression that a more casual fan knows more or enjoys more of the band's work than they do. It's a matter of choosing how to say you appreciate a band and/or their work. As George Carlin once say, words are all we have.
In my younger days, I can admit being a huge gatekeeper of many fandoms but I've grown to see how bad those types of fans can be, because fans start as casuals, and we develop into hardcore fans over time. Rather than gatekeeping, we should nourish new fans with songs they haven't heard yet, give them new albums, share our (sometimes overly obsessive) love for the bands we love, and get them to JOIN US in our love, because it's always a joy to be able to gush about the things we love with new fans.
Just don't go shoving Queen II into the face of someone who has only heard of Queen because of the movie...ease them in a little!
-Marc.