Oh look, the boy doesn't want to share the playground with the girls. Boohoo!
Webnovel releases one male-lead and one female-lead per week. Male-lead books already have an advantage over the female-lead books, having been the majority of translated works from the beginning. I don't know what you're complaining about as there has been no decrease in the number of books being released "for guys," and if you're complaining about a decrease in quality, don't blame that on the females and on what they read. Blame it on management and the translators and editors. It's not like the female-lead books are top quality anyway.
The influx of females here made the market expand. It didn't limit your choices, it's just that your taste is not the taste of the majority anymore. The books that you read are still there. If they ever disappear, then it would be because those kinds of books don't get enough suppport, and that would not be the fault of the females but the fault of supposed fans who didn't show their support.
Take the translator of LOHP and The Beautiful Time With You: he posted on TBTWY that he would be focusing more on LOHP because that's what pays the bills for him. So I don't know what you're on about that translators will be neglecting "male-oriented" books just because there are now more "female-oriented" books and more females here. If a story is good and people support it, translators won't drop it in favor of something else (there could be other reasons for dropping but certainly not what you were implying).
Basically, money speaks, and if you're really that concerned, then open your wallet and let it speak. It's not as simple as supply and demand. As long as there is a market, no matter whether it's niche or mainstream, minority or majority, someone will serve it. And qidian will not be foolish enough to get rid of the male market as long as it is profitable. That's the reality of life. Stop blaming the females. It's funny because at the same time you say it does not matter if a female reads a male-oriented book. Basically you want males to be alone in this. You want webnovel to be the playground of men like you think it used to be. Things change, and women make up half of the world population. Deal with it.