My experience with my female relatives (and to be fair, a number of the males too) is that they don’t like the faff of grinding, weighing, nor inevitable spillage of coffee grinds on work surfaces, grounds tide marks in sinks etc.. Generally preferring Nespresso/capsule machines, or French press/Aeropress/Clever (most frequently using pre ground).
Most of the interest on coffee forums is really espresso/machine/grinder focused, rather than ’coffee, or ‘specialty coffee’. Oftentimes, increased complexity and accumulation of gadgets is a focus…not sure that this is necessarily attractive to casual coffee drinkers of either gender.
The ladies I know seem very happy to have & enjoy specialty coffee when made for them at home, or out in cafes. I’d pop into a bunch of cafe’s and do a quick headcount.
So, I’d expect the level of female involvement in forums to be natural fall out as there aren’t any restrictions on female participation. Is there even a requirement to state your gender when joining a forum (I don’t see why there should be)?
I think forums are a small % of coffee drinkers, so you’re starting with a skewed sample.
Maybe interview a random sample of women to assess how many like coffee, how many make it themselves & how many are interested in online forums/coffee forums.