I have a theory that dynamic programming problems have become more popular in part because the lower hanging fruit — reverse a linked list, is this a palindrome? — have become widely known and practiced via books and sites like hackerrank.

DP problems represent the next rung of the ladder, are somewhat less familiar. And most importantly, satisfy an interviewer’s possibly sadistic impulses by presenting a problem that has an easy 2^n solution. ;)

Sarcasm aside, I think this is just the inevitable result of the systemisation and gaming of the whiteboard interview.