Nope, where a family might struggle to efficiently manage 50 acres under continuous cultivation even just a few hundred years ago, now it’s not uncommon to see single family farms with 20,000 acres each of which is several times more productive.
It’s somewhat arbitrary where you draw the line historically but it’s not just maximum productivity worth remembering crops used to fail from drought etc far more frequently.
Small hobby farms are also a thing these days, but that’s a separate issue.
For those 20,000 acre farms, by what measure are they more productive?
In my experience they're very productive by poundage yield, but horribly unproductive when it comes to inputs required, chemicals used, biodiversity, soil health, etc.