None of them are seventy:
Ford (b 1942)
Stallone (b 1946)
Seagal (b 1952)
Chan (b 1954)
Willis (b 1955)
And the lion's share of their work as action heroes came when they were in their 30's-40's. The only reason they've gotten work in action flicks in their 50's-60's is because of their body of work from their younger days.