First of all, I think it's a bit faulty to say that progress is good by default, as it is only good if it leaves society in a better state than it was before.

I'd actually argue that progressivism is, in general, pretty regressive, rather that leading to progress, and has led to things like sexism and racism coming back into favor, rather than falling out of favor. This has given us a society where there is now a fair bit of progress needed to get back to where MLK wanted us to be, with people being judged by the content of their character rather than the color of their skin (or their genetalia). There are other things too, such as a return to science, the presumption of innocence before being proven guilty in the eyes of the general public, and more that need to be strived for, but progressivism attempts to take us backwards in regards to those things, rather than taking us forward.