I believe fig makers already use 3D printers for prototypes. I've seen tons of unpainted and unreleased figures with those very obvious horizontal printing lines. I'd like to think it helps a lot in the pre-production phase. I don't think it's changed the market much though, but might be why we've been able to have nicer quality figures these days if nothing else.
For home use, you'd need a pretty good printer and the right materials. You would also need to do a considerable amount of work on the figure once printed to make it passable. Sanding and smoothing the entire thing for starters, and of course painting it. This wouldn't really be anything new for veterans who are used to a time when nearly all figures were garage kits, but people who expect to hit a few buttons and get a perfect figure, they might be in for a surprise.

3D printers are really only good for primitives and base models that you plan to use only for the general shape, and add on all the details later.

Somewhat related.

https://soranews24.com/2021/03/15/want-to-design-your-own-anime-figure-and-have-it-shipped-to-you-cool-program-lets-you-do-just-that/