Confused, There's a "sticky post" ( = permanent post) with the ACR criteria to classify systemic lupus, near the top of the thread list. In it, you'll see "photosensitivity" is only 1 criteria of the 11 listed. To be Dx'ed with systemic lupus, you need to match any 4 of those 11, sometime in your lifetime (but not necessarily all at once).
This list also illustrates that photosensitivity is not "required". Why? You could have some OTHER 4, excluding photosensitivity, but still have SLE. Which is pretty much what the responses so far are saying, actually, that some are photosensitive but some aren't. (I am, horribly
FYI, there are "lesser" forms of lupus where you don't meet "4" on this ACR classification list, like SCLE (may meet 4, but maybe not), or DLE (typically fewer than 4). You could be photosensitive with these forms, too.
Take good care & best wishes! Sincerely, Vee