I think what you are seeing is a push back against radfem beliefs that any woman can identify as (or in their words "become") a lesbian if she abstains from sex with men for political reasons. So their belief (or at least the mainstream radical feminist belief) is that a woman that is attracted to men but chooses not to have sex with men is a lesbian. It's called "political lesbianism" but these days they just call themselves lesbians rather than political lesbians and it is now predominantly bisexual women who choose to only have sex with women because they hate men who call themselves lesbians. They redefine being a lesbian as being about hating men and have basically created something call lesbian feminism which doesn't really represent the interests of or experiences of actual lesbians. And some of them are genuinely lesbophobic. But you can't challenge their lesbophobia or say that their feminism isn't actually representing lesbians because they all identify as being lesbians. Meanwhile on the queer side, you also get both heterosexual and bisexual women who identify as lesbians (eg because they are dating a transbian who finds that validating) and shame actual lesbians as transphobic genital fetishists because we're not attracted to males. It's not surprising that many lesbians are now trying to gatekeep the language under these circumstances. It's not meant to exclude actual lesbians who have had sex with a man in their past (although some people want to muddy the water by claiming it is) but I think it does make lesbians more wary of someone who has had a lot of past male partners and says they are a lesbian and, if I was getting to know someone like that, I'd probably want to weigh them up to work out if they are either a) man-hating "political lesbian" or b) one of the queer words-mean-whatever-you-want-them-to-mean types. In my case, I would be open to dating a bisexual woman but someone who lies about their sexuality or potentially thinks that words just have no meaning and everyone can just identify as whatever they want definitely isn't for me.