I think its simply a function of getting older yourself. Its probably a combination of things. Getting closer to your own mortality, seeing or hearing about others your age dying, being around long enough to have the cumulative effect of tragedies prior, and just simply getting more emotional in general. Maybe its from declining T too.
I have found the same in my own life. Getting misty eyed over things I would never ever have. The amazing quality of a good song and singer, more enjoyment with things like theater and classical music, even opera dare I say, when there is zero chance 10 years ago Id have cared or enjoyed even a little, any of these things. I think its just the realization of amazing talent when it exists, beauty in nature and knowing internally that your time on this earth is short and taking time to appreciate it all.