Many retired people need help with what others consider everyday (monthly, yearly) tasks: changing filters, fixing a door, light bulbs, or minor electrical fixture/switch/appliance repair, stopping ants entering the building, a leak in the ceiling, etc. Fixing PC problems counts too.
Anyone who has owned and maintained a home is capable of doing these things provided they're in good health. I'm always happy to help my retired neighbors with their little problems, perhaps b/c I don't have enough of them and they are an interesting distraction, as well as making me feel helpful.
There're lots of older / retired? people at a library here where I live, two evenings a week, meeting younger people (say 15 to 35 years old) who recently moved to here, with learning the local language and school work.
There're younger volunteers too, helping out with the language, maths, chemistry etc — but I was surprised to see that many older & retired people, maybe 70% of the volunteers. (This was before the virus, now I think libs are closed.)
Just like you can do a 3km/2mi leisure bike ride, or bike ride for strength (eg sprinting uphill) or endurance you can do the same with gardening.
I am also guessing you've never covered any serious area with a garden hoe. :)
But after they sold the house (he loved gardening) and moved into a condo where there is little to do she can see him going downhill month by month. Before he had a purpose in his life (gardening and house maintenance), now he just has the sit around or go on bike trips. It is a shame.