To the first statement, I say nonsense. It has nothing to do with retreating to the egotism of adolescence but everything to do with recognizing that drums serve a different role from that of melodic instruments. A guitarist can't change the key of a song, or make dramatic alterations to his or her note selection, without transforming the piece into something almost unrecognizable. A drummer, on the contrary, can often employ an eighth-note fill instead of a sixteenth-note fill, and nine out of ten listeners won't know the difference. Other drummers might, but they make up a negligible percentage of most audiences.To think “well the original guy doesn’t play it the same, why should I?” Is just an excuse to be 14-years-old again. Even arguing that we shouldn’t have to cover the fills as recorded doesn’t really fly because, as I said, the other musicians are playing it note-for-note.
So let’s just say there’s some room for “adjusting to taste”, but to throw down the “who cares?” argument is probably not in the conversation for people earning a good income from their music.
In terms of the second statement, I don't know that we can make sweeping claims about what works or doesn't work for drummers "earning a good income from their music." As stated previously, we see countless examples of well-known players who don't strictly follow the parts they've recorded. If you want to dress up and pretend to be a band you're not, I can see an argument for carbon-copying recorded drum parts. Otherwise, that mission is often without essential merit. It's a choice at best, not an edict.