Rav Sternbuch writes in Halachos V’Hanghogos, that if there is only one choice between opening a Kodesh school for girls or a kodesh school for boys, the girls Kodesh school takes precedence nowadays.
The reason is that the street influence has become more immoral,since World war 1 (which Chofetz chaim said the world fell tons of Madreigo’s after), and ‘sechof’ (garbage) of foreign ideals which penetrate into the Jewish homes, women like Sarah Schneerer, it is known all the opposition to her movement, faded after World war 2, and a Rabbi i hear Shiurim from said, if you are going to Poland make sure to visit her Kevurah, she is responsible for tens and thousands of Bnei and Bat Torah and many more for eternity.
Although Chofetz Chaim himself said women should only learn (many types of ) mussar sefarim (which is based on a Rishon that says this), i suppose the street influence has become worse, and top Gedolim have given Haskomas to organisations like Or Navva which teach women many types of Torah.