2013 Rockshox SID XX 120mm - stiff/seems to stick

I've had this fork since new and have serviced it myself through the years. It's always worked exactly how I expected until I got a new bike and stored this one. It hung by the front wheel for about a year and after getting it back out, the fork seems to judder on compression and sometimes stick and not compress at all.

I pulled it apart and did semi-complete service on it. Change the fluid, greased the seals, lubed the foams but nothing else. Nothing looked bad internally, seals were soft and foams were still good, plus it was serviced not long before I got my new bike, so it had hardly any hours on it before it went into storage.
After the semi-service, it still does the same thing.

I'm going to pull it apart again, but I'm just wondering if there's anything specific I should be looking at this time. I just can't imagine what might have gone bad from hanging.