Of course we don't know exactly how long we'll live, but around 80 seems reasonable for fit health conscious people. Do you plan to run until the end? I hope to for sure.
We all run for different reasons. Is living longer one of them?
https://runnersover50.com/blog/does-running-add-years-to-your-life-what-the-research-actually-shows/
I’ve been running for 30 years and I keep going and I see lots of people my age will run regularly. I also see people much older than me in their 70s 80s and 90s even finishing races.
So I wonder is there anything different about running over 50 then before 50?
Have you noticed any changes?