What learnt in school is insufficient to meet with all real world challenges. To claim as a developer, you need to understand the internals, that is the ability to poke and trace to the root of the problem deep underneath.

Debugging in FP feels different to most people, where our thoughts is tuned to the procedural model with observing states and form our hypothesis from there.

Another disadvantage with niche programming language is not enough Stack Overflow help there. That alone will drive most people away.