That's why I would prefer photos at their prime success rather than a recent photo...
Currently we have no guidelines for picture exactly to upload, but it's an interesting discussion.
Why at their prime success? Why not at the peak of their success?
At "peak" of their success would be ideal provided it is a very common "iconic" and immediately recognizable photo.
Incidentally, I thought "prime" meant at top of one's performance actually (based on "prime time" on radio and television, meaning top listening and viewing time...) But I may be mistaken... Does "prime" mean beginning of their careers? I didn't know that. In any case, I mean picture from their best-known period.
And contrary to some opinions, many of the faces, of even renowned artists, are not known by the new generations anyhow. The generations of the 2000s would hardly know, in general, the pictures of the artists we assume are well-known from the sixties, seventies, eighties and even the nineties... let alone songwriters and lesser known artists who remain unknown in general.