I saw him in Berlin last Tuesday about 90minutes plus encore. Great concert most of the hits and some new ones, though not sure about the three song medley near the start. Full band with a couple of backing singers and small horn section. Voice is still good although maybe a bit strained on the higher notes.
He may struggle with the pop expectations of the "legend" slot, but he uses the songs well to get some political points across, which should appeal to the ethos of Glastonbury, especially on Mathew & Son (Labour and Work relationships), Where Do the Children Play (Environmental), Hard Headed Woman (Female Empowerment) and a tribute to Nina Simone Please Don’t Let Me Be Misunderstood (Intolerance to different opinions)
His fans will love it, those who know some his stuff will enjoy it, not sure how it will appeal to the curious.
https://www.setlist.fm/setlist/yusuf-islam/2023/zitadelle-spandau-berlin-germany-4ba6c75a.html