There was a thread last month about this topic:
https://www.photrio.com/forum/threads/expired-color-film.200316/
I generally am in the line of the discussion, and even more so given the effort. People are also paying crazy amounts for old film. I would however be curious about films that aren't anymore available (Agfa, Konica, etc) and recently was thinking that I would have liked to test one of these Konica films!
My only positive experience was from Astia 120 exp 2006, developed 2020 but always frozen. Perhaps you can do something toy camera or more experimental with it.
I also had a positive experience with some Fuji Astia. Mine was 135, frozen in 2010, thawed and shot in 2019 <
results here> For me, this is the most painful possibility that arises from shooting discontinued film - what if I really like it?
Thanks for reminding me about that previous thread. I think I might have skimmed throught it, but at the time I did not have any reason to pay close attention because I am not really that interested in color negative film right now. I do enjoy color photography, but I tend to prefer digital for that.
There may have been a time in my life when I would have been delighted to do the experiment just to see what happens, but I guess my spark of curiosity has gone out. Or maybe it's just that I have less time to waste now. For the past few years I have been concentrating on trying to find my one-true-b&w-film, with the intention of shooting only that for a year or two. With that goal in mind, color film is something of a distraction for me.
So, I am beginning to think this expired color film may be worth more to someone else than it is to me, and I should just put the whole lot up for sale on eBay. In early 2020, I bought 5 rolls of Portra 160 - of which I still have 2 rolls left. That lot has since expired (12-2021. I think I will bundle the Portra in with the Konica film, for sale. It is kind of a relief for me really, to be released from the obligation of shooting this color negative film, which I just don't care that much about.
But the thought of making money from hobby - as opposed to spending it - is going to take some getting used to. ;-)