Yeah, I don't understand this whole "be positive all the time" thing either. Even decades ago when I lived in Germany for 5 years, I became aware that many Europeans grumble about Americans smiling all the time. Even then, it was like culturally we'd been conditioned to fake cheerfulness.
Some of my German peers thought it was a little weird, to be honest. Of course some of that is just different cultural expectations, but ...
We seem to have gotten to a place where smiling and cheerfulness are obligatory, even in the face of serious problems that need fixing. To the point that people feel offended if you aren't helping them feel cheerful.
This is a real problem.
The world's problems don't get fixed by smiling at them. They just don't. They get fixed by facing up to them and taking action.
When I was helping fix the HIV/AIDS problem back in the early 90s, do you know how often my colleagues in Act Up and I were smiling and cheerful?
If you guess, "pretty much never," you're right. We had serious work to do and very little time to smile and try to make people feel good. Instead, we worked hard to increase awareness and make people feel really BAD. So they would help us.
And guess what? It worked.