???Modern Speakers???Life Expectancy???

Yes- we expect your speakers to last with no problems 

No- I haven’t heard nor seen any speaker longevity products and/or tweaks. People usually replace the speaker, a few repair them.

Wishing you the very best for your health- hope it turns for the better.

Some foam surround types do seem to degrade with movement (i.e.: excursion) as well as from the exposure to UV-radiation and atmospheric conditions, but more modern polyether-based foams last decades, and when treated with foam guard are very resistant to UV-radiation and other external factors.

This is very interesting, would you care to elaborate a bit? I’ve always been reluctant to even consider speakers with foam surrounds fearing for their longevity - e.g. Cube Audio Nenuphar or Gethain. What to expect from such speakers in terms of longevity?

Sorry for the (relative) off-topic.

I just gave my brother a 23 year old pair of Sonus Faber Concertos that still lookand sound great.  

Time can take it's toll on certain things like surround material and glues but it seems those speakers have stood the test of time.   

Fortunately 8 years left on my main speaker warranty and 10 on my new Omega so hopefully don't have to worry for a while.