Dying tragically young seems to create that sense of being greater than they actually were at the time of their death. Without any new material, ever, we have nothing to rate someone on, and mourning that fact, we boost someone to legendary status. How you feel about him is similar to how I feel about Stevie Ray Vaughan. No question SRV (as he's referred to by those who think EVERYBODY should know that) was a great guitarist, but there have been and are a lot of great guitarists. I like some blues but I was not a great fan of his style, so naturally I am going to rate him lower on the list of the greats. I was not also a big fan of Quiet Riot and later Black sabbath, so Rhoads is also not very high on my list.
That's me. You are you. The whole thing is subjective anyway, so I tend to avoid arguments When asked, I'll just say who I liked or like. So, I can't say that Rhoads, or anyone, is over-hyped, overpraised, over-loved.