It's an issue now for plenty of people interested in XC and other races - you may have missed the debate about the LDMT trophies for example? Women running shorter distances perpetuates a (hopefully outdated) message that they're not as capable as men, as that's where different distances originate from. What equalising the distances would 'prove' is that the organisers don't believe this. It's an atavism that is straightforward to rectify and hopefully one day will look as archaic as women being excluded from full-length fell races.

If it's just a glorified parkrun, great, let's all run the same distance