Just came back from Japan and I found it vibrant and modern.

If you went to Japan in the 90’s, 00’s or 10’s, you’ll find the issue is that Japan still feels mostly the same. It’s a wonderful country, but post-Japan’s asset bubble and crash there’s been noticeably less change.

Change for the sake of change is what cancers are.

Why does it need to change?

Did you visit the countryside?

Japan has an aging problem and a big misogyny problem too.

Name the country and I will easy find the spots where it is not vibrant and modern, and then say "did you visit those?"

Say, I heard France has great cuisine, but I had street food in Paris and it was meh.

Doesn’t change facts about Japan‘s problems. In certain parts they are just less visible.