I used to be the guy who would say that people need to stop writing code which others can't understand, but then I migrated to, "why am I working at a company where I need to lower the bar so much that making changes in a code you understand well takes ages".

I joined that school when I used FP for my own project (I use Elm, and RamdaJS+JS) and found how amazingly handling bugs and complicated logic became. This clearly came with a higher barrier to entry for other people to understand my code (but this cost only needs to be paid once, I look at other people's functional code and I got no problem understanding it btw).

I understand large companies where logic needs to be written so simply so that anyone can understand it (Python philosophy "Code is read a lot more times than it is written"), but they don't end up with fewer bugs, it's just a LOT LOT BIGGER codebase, with 5 million for loops, doing 1500 things in one for loop.

In fact, before I fully went to FP side, I started writing my JS code without using for loops or forEach. Even this simple change of writing code using map/reduce/filter/drop/reject/take etc made code lot simpler to maintain, reason with, and eliminate bugs.