https://www.frontiersin.org/journals/nutrition/articles/10.3...
A lot of times the issue is just logistics. Many of these are tropical and don't fruit at a predictable, narrow time of the year. Making it hard to time when you hire a bunch of labor and do your harvest.
Then ofc there's always the marketing problem of convincing people to use this new plant
I ordered some flour and put it in bread and other things. It’s a sweet flour that tastes like a very interesting chocolate.
It’s just hard to harvest, and to mill, and not a lot of people are willing to eat different things.
But the tree thrives on less then 8 inches of rain a year.
It's also got some of the deepest roots of any plant ever and can spread rhizomatically. It was introduced into the old world to hopefully fight desertification but has ended up being one of the worst invasive plants ever introduced. You'd basically need an excavator to get rid of one once established