You have a point.
Having lived in Taiwan for several years and traveled to several times to Hong Kong and Macau, Putonghua always has always gotten me by, but I have never been able to understand what the locals are saying to each other (in Taiwan, outside of Taipei)
Then I visited Beijing and it was remarkable. Communication was no problem. I could understand a good part of nearly every conversation I overheard. And no taxi drivers telling me I had to learn Taiwanese. it was nice.
Still couldn’t flush the toilet paper though. 