Many people with all kinds of political views write on this topic. Some of those wider views I find ghastly and poisonous, just as I find the views of some very famous writers in history ghastly and poisonous.
The question when to stop paying attention to the work of someone I disagree with on many other issues is an important one. So far my current choice is still case-by-case (Tolstoy didn't think much of women, for instance, but I still reread his books, while remembering that he wouldn't have been impressed by me being one of his readers).
When it comes to the redefinition of 'woman' and the erasure of the female sex from all language (and, ultimately, from being able to unite in political activism) many anti-feminists share views with us, but for diametrically opposite reasons (though some may have changed their views towards less sexist ones, of course).
Their arguments can therefore be valid, depending on their research and thinking skills, but I never forget that they share some of our concerns because they wish to keep us subjugated as a sex. So it's not a good idea to join hands with them, but it's not a bad idea to read their arguments keeping this context in mind.
It's like the GC feminists and the anti-feminist right were fighting duels at dawn and the gender identitarians came and stole all our pistols. Both sides want those back but for opposite uses.
In any case, many basic ideas in gender identity ideology are very much like those in retrogressive anti-feminist arguments, such as the belief in the essentialism of gender stereotypes, the idea that 'women' should behave in feminine manners and define themselves as feminine people (look up some definitions of femininity and you can see why that would kill most feminism as feminine means, among other things, being submissive and passive).
So in this three-enemies battle everyone shares something with each of the three enemies and sometimes is drawn to awkward temporary co-operations.