I get that there could be any number of sound reasons for someone to want to get that kind of detail about their seat mate in advance. Another could be passengers with allergies to dogs wanting advanced notice about a passenger travelling with an assistance dog. But given the question was partly phrased as a "should", my response is still no, the seat map should not give away any detail about those seated near you. Seat maps should simply indicate whether a seat is or is not available to select. If you and your neighbour can't sit together - for whatever reason - an on-the-day swap sounds like the right approach.

(Also, in your example, which I know wasn't the original ask of the thread and was about accommodating religious requirements, sadly we live in a world where if the seat map indicated there was a solo female traveller, that could potentially attract some unsavoury characters to select the adjacent seat).