I agree with everything you’ve said, but modern technologies aren’t the only issue. The fact is that many food crops are hybrids that don’t breed true, and it’s been like that for many decades. That is, you can save seeds, even legally, but within one or two generations the plants revert to form, losing their desired characteristics and “hybrid vigour”.

To the best of my knowledge, there is no such thing as a GMO wheat. Yet saving seed at scale hasn’t been viable since at least the 1960s.