Check out realseeds.co.uk if you are in the UK (or even if not they may still post abroad). Their catalogue is made up of open-pollinated varieties for saving your own seed from. They even have some open source designs for seed-saving hardware and are very based. In fact most of the veg currently growing in my garden is fourth or fifth generation from seed I bought from them is and is adapting to my local conditions.

I think you make a great point about not having regional seed suppliers. This is a deep problem that globalism has created, in that we just don't have reliable local seed suppliers and most of our seed is coming from a very small number of sources.

We had this issue going into and throughout the pandemic, where luckily we had hundreds of surplus seed packets because we are dorky hardcore Gardner's, and we were able to supply our community. However seed quickly ran out from both big box and online retailers. Likewise most people don't consider what makes calories happen from what's fun to grow. Like good luck powering yourself for a day on tomatoes. Y'all mother fuckers need beans.

Also, a follow on issue that the pandemic exacerbated that were only out of now, is that workers for the pollination green houses became in short supply. We only really came out of that in the 23 season. Need people for manual pollinated varieties. No people no pollination. Like not an issue now but def a consideration.