With the new HTTP/2 protocol the overhead created by repeated HTTP requests to the same server has been greatly reduced.
With this in mind, are there still any significa
Minifying JS can still reduce the size of many symbols; inflatedJargonSymbolizerTokenManager will become _a. One example I found showed that JQuery GZipped was still twice the size of JQuery.min GZipped.
I also want to note that while you didn't imply otherwise, dystroy's comment is correct, and in fact contradicts the badly-written Wikipedia explanation; "Concatenating" JavaScript files might be less useful now. Minifying them still has its benefits. Just wanted to mention that, in case you happened to get some information there. In fact I'd edit the page myself if I wasn't worried about getting into an edit battle.
CSS likely has fewer opportunities for symbol reduction. Theoretically, all it would get is whitespace and comment removal.