If a country with a population of around a million (or even as small as 100k) enacted UBI I would take those results to be representative of a societal change.
I honestly doubt you would. The typical arguments of:
- it's not comparable to a country of 350M, they're barely as big as $cityWithOver1Million
- their society is very different from ours
- their implementation is different from what we could ever manage
- the circumstances were different
would come around.
You're making exemplary conservative arguments to stalemate progress by creating a chicken and egg problem.
- Won't accept results of change in a small environment because they aren't representative of change in large environment
- Demand results of change in a large environment before applying them to large environment
- Won't apply changes to large environment because results of change in large environment don't exist