i don't like it either. play the full song or don't play it.
I don't automatically hate medleys, and they don't necessarily mean full songs don't get played - eg, see all Cage medleys. Plus, good use of fragments can work well. I thought the Mama tour Cage medley created a lovely surging dynamic sequence.
Being realistic, given they're a band who preferred to focus on new material they'd find it difficult to make enough room in a set if they did a couple of complete 70s-era 10-minute songs. I'd have liked that but totally understand their thinking and it means you still get to enjoy some of that stuff even if partial rather than whole songs.
Where I think it didn't work so well was eg the 92 medley. It was a striking diversion from the established Cage sequence but ultimately frustrating to not even get a whole Lamb or the "whole" usual Volcano segment. The band later said the snippets during the IKWIL segment were a mistake. From what I know of them the Mama tour non-Cage medleys, while interesting on paper, didn't work too well. Playing just the intro to Mar before going into something else is just going to raise fans' hopes then piss them off. And it's a bit Vegas/cocktail-lounge.