The only time I will even consider squeezing into the old uniform (it's been almost a decade since I retired) would be a military event in which I have a role.
For example, I commissioned my nephew last year when he graduated from college. It was an extremely proud moment for me, and I made sure I could fit into my service dress for it.
However, for anything else, I will wear the appropriate civilian attire.
Plus, that way I don't have to shave!
Cheers! M2