I mean there probably are lots of reasons why we farm only certain plants.

For example dewberries have short harvest window and as far as i know they need to be hand picked.

There are many reasons, but it all comes down to economics: how easy and cheap it is to farm and harvest, yield size, does it require refrigeration during transport, what’s the shelf life, etc. Unfortunately optimizing for economics rarely pairs well with user interests, e.g. How nutricious the food is.

About shelf life:
There’s this weird little apple tree, Prime Rouge. Every two years, he’s choke full (the other empty) of perfectly formed, perfectly red apples, optical flaws are rare. They are already edible in summer but get really succulent taste and a white flesh about two months later. The best apple breed i know, in texture, taste and look.

Buut they only keep about two months max, unlike the other breeds you have in your supermarket.