Personally I instinctively hated that idea when I first glanced it in my FB feed, and there is NOTHING novel about their ”solution” of encoding number strings to word strings. That this process isn’t open and deterministic is a HUGE red flag to any semi-technical person. Or should be.
API niceness is irrelevant when service is useless. Wrap a turd in gold paper, it’s still a turd. Your Royal Mail APIs can be whatever, but at least you won’t need to pay to find out your postal code. Your postal code system isn’t funded by VCs.
Just take the word of people who DO have a clue.