Actually, I was a Shangri-La Circle Diamond member in 2023, but only did ~30 nights that year. As a consequence, in 2024, I was demoted to Jade. You are right, the official benefits are not that much different, except for the Lounge access with Diamond status. For me, a very useful benefit of Diamond is 8am checkin/6pm checkout. These are "upon availability", but I have never been denied in the cases where I have had to use it (especially 8am checkin). For late checkout, I have rarely had to request anything past 4pm, and I think in only one instance did I ever request 6pm (that was at Shangri-La Far Eastern Taipei).

As a Diamond in 2023, I was frequently upgraded to suites, and not just to a "better room". As a Jade in 2024, almost every booking has been upgraded at least one room category. As I mentioned above, the Pudong Shangri-la has been treating me as if I were a Diamond, by giving me several room-category upgrades AND also Horizon Club access.

These few posts are probably getting off track, so Moderator, please feel free to move to Shangri-La Circle Forum if needed.