Since it bears saying it again:
1. Don't throw around the term "fujoshi" if you don't know what it actually means. Research its real meaning before using it.
2. Don't join the fandom of a bl story (as mxtx's novels are) and then be surprised that there's bl fans in it.

3. Don't assume the identity of bl fans. Don't immediately think they're straight cis white women, because you'll find that most of them actually aren't. And even if they are, there's very few that fit the stereotype of a homophobic fan who wouldn't support real lgbt+ people.

If you believe that BL as a genre has problems, then I invite you to examine them through thoughtful critique. This means researching the history of the tropes and the place a story takes in the broader context of BL and romance. The lens of a theoretical framing might also help.

Actual critique also doesn't attack readers nor authors for what they like, because it's important to recognize that there are as many different human experiences as there are people in the world. *Attacking* is never the point; *understanding* is.

If you're genuinely interested in understanding the origin and meaning of the term "fujoshi", I recommend this as a first reading on the matter: https://twitter.com/ouyasumi29/status/1163664650329886720?s=20

If you AREN'T interested in learning the actual meaning of "fujoshi", then I can only answer you with this: