I’m so glad to hear about females living more than a couple of years! Most of my veiled females lived to be 6 or 7 years of age. I’m sure putting them on the “diet” and temperature control we talk about on here helped that to happen. Most of them did not produce any eggs once they were set on “diet mode” as well.
My success with panthers was less in that I could not get them to stop producing eggs but just to decrease the number of eggs in each clutch…but I was “afraid” to push them as hard as I did the veileds.
The studies by veterinarians on follicular stasis and dystopia that started around 2008 are still continuing, but there still has been no solution determined by the vets to prevent both of those issues, sadly.
Chameleons definitely do show their age to us if we are observant…arthritis, etc can be found in them, just like in other critters and humans.
Not enough studies have been done about their aging though.
Just a few things that might help…To keep it comfortable/help it in the meantime, if you keep it lower in the cage so she won't fall, please make sure you move the UVB light lower and make sure she doesn't end up sitting under the basking light, unable to move out of it. (I'm sure you will know this already...but...)
I do think that chameleons (panthers in particular) develop arthritis in their old age....no proof, just my opinion from seeing senior chameleons over the last 30+ years.
Reptiles are very stoic and show few signs of aging, but subtle changes in behavior, or mobility, or reproduction, or weight, or appetite may all signal the beginning of old age to a caregiver who pays attention.
You've done well so far to keep her going!