I’ve heard several versions of this same argument for decades, and they all (ironically!) suffer from misidentifying the problem. While there is a theoretical need for taxonomists on a societal level, no one wants to pay for them, so there are few jobs and many trained people leave the field.

What’s the point of training people to become botanists when they can’t get a job in botany? Governments must create new positions. Then the training programs will follow.