Bitcoin is actually inflationary, not deflationary.

I guess it depends on what your definition of deflation is. But if you consider deflation to be a general decline in the money supply, then bitcoin's currency level actually never goes down. There is a constant increase in that, each block that's been mined.

However, the level of inflation just slows down over time due to halvings.

We could see potential deflationary issues when bitcoin nears its supply ceiling, and the rate of lost coins exceed that of new coins coming in, but even then it's unlikely that it'll affect any single country as bitcoin is global. Besides, if bitcoin serves as a niche, safe haven asset in the future for those who want to save their wealth in the long run, there is nothing wrong with its supply being capped and potentially even decreased, just like gold. It's a store of value - after all.