Recraft has a style feature where you give some images. I wonder if that would work for icons. You can also try giving an image of a bunch of icons to ChatGPT and have it generate more, then vectorize them.

Recraft's icon generator let's you do this.

https://imgur.com/a/BTzbsfh

It definitely captures the style - but any reasonably complicated prompt was beyond it.

I think the latter approach is the best bet right now, agree.