To be fair, wiki counts one of the male characters twice (as main character ash tyler and 'recurring' character voq), and there is more to the question than just who is officially a main character, since 'recurring' character Spock left several main characters in the dust this season. Personally I'd say 'Recurring' characters Cornwell and L'Rell also outshone at least one main character last season, too (Culber). And there's no denying that Burnham is very much a lead character, not an ensemble character - which Trek hasn't really had since TOS.
Having said all that, however, I have to agree that for all the promotion and interviews that were done about how DSC would truly respect and embody diversity in a way that Trek hadn't done before, my initial reaction on seeing the show was they didn't go anywhere near as far as they said they were going to (and really only barely went further than other Treks had already) and it was all very disappointing in that regard. And the general make-up of the show's demographics haven't significantly changed since then.
We can talk about a truly female dominated show when the season long 'guest' spot(s) goes to a woman(women) and Tilly doesn't get shunted to the background and Nhan or Reno or Detmer or Owosekun (or all of the above) actually get real parts - and even then, only if all of this isn't compensated by roughly equivalent developments for the male characters.