Mass page builders with thousands pages duplicate content?

Does anyone have experience in creating thousands of pages of duplicated content on the same site with only changing keywords for each location+service? I seen them working a few years ago but is this still a good solution for local SEO? Will google index all those duplicated pages?

Based on some sites i have seen, seems like its still working for local seo.

Some sites have SHIT links, other have some natural and PBNs.