I agree with your sentiments, which are both reasonable and articulate.
It is too unreliable on the client side to know if it works.
My users also wanted this functionality for a newsletter to try to increase engagement further down in the email. I've always had negative experiences with anchors in emails - using them didn't always work and creating them was a gamble. How annoying is it when you click one and your email client doesn't support it? You never blame the client, always the sender.
I told my team it wasn't possible at this point until more clients allow it's usage.