I have and like “PDF Squeezer”. But I’ve been unable to get the command line interface “pdfs” working as when I click on the “grant access” button, PDF Squeezer throws the error “The Open file operation failed to connect to the open and save panel service”. Have no real clue what that means. Have contacted their support a couple of times last month with no reply whatsoever. Nice.
Otherwise, dragging and dropping individual or even groups of files does a good job of “squeezing” PDFs down to more reasonable size for my purposes.