We all agree terf has not been a useful term for a long time, it implies they're feminists, it implies they're for women, it reinforces their arguments that they're on the side of women and gives them space to hide their more extreme elements.
Why not something like cis-supremacist? Something that is far-right adjacent would be useful in making people properly make this connection, especially given who they're allying with lately.
before people who didn't know the details got hold of the term, TERFs were people like those "womyns music festival" types and were genuinely interested in abortion rights, girlbosses (before we had that term), workplace equality, maternity leave, having a seat at the table of power, and so on. all for cis women of course, because trans women don't exist or supposedly don't need any of those things.
we differentiate between white feminists and meghan mccain, we used to differentiate between TERFs and antifeminist liberal transphobes, but a bunch of people didn't and the "but i'm a feminist" transphobes don't seem like they're doing much feminism anymore, so here you are wanting a better term.