Would be better to introduce genetic incompatibilities so that GMOs were infertile with non-GMOs.

I guess if that was your goal they would probably have to insert a novel gene that wouldn't be present in say, the over 10,000 different varieties of conventionally bred tomatoes and then engineer the plant to produce sterile seeds, but that seems like a much more concerning trait to let out into the wild than beans expressing umami flavor. Terminator seed technology has been around for a while but as far as I know there have been no commercial applications because it worries a lot of different groups.