Even for most 60+ guys, 12 minute mile pace (5 mph) is a slow jog, a warm up pace for sure.
At 67, I spend cold days in the gym on the treadmill. I start my runs at 5mph, and gradually increase speed. By the end of a 40 minute run, I will be running at 6:40 mile pace.
I have friends who are over 70 who still knock out sub 7 minute miles. Also have friends who never run under 9 minute mile pace.
The important thing is we are still running. We don't put too much emphasis on race times or places. 50 years from now, nobody will remember who you were or what your PRs were either.