The biggest demand for Bitcoin right now is store of value. Growth of price makes it raise even higher. Price will rise much higher when countries will start buying in.
Actually, the main source of Bitcoin's demand is still coming from speculative use. Only a very few people actually use Bitcoin as store of value right now, but it's slowly gaining traction. In order for people to use Bitcoin as store of value, they first need to stop focusing solely on the speculative aspect and start diving into what's making Bitcoin such a powerful multifunctional tool. And what exactly do you mean with countries start buying in? Are you referring that governments will start to acquire Bitcoin just like they do so with gold to increase their reserves? Theoretically this could be possible, but there is no way for us to find out until they publicly announce that. Japanese authorities technically hold +100,000 BTC from MtGox, and Bulgarian authorities have said to own around 200,000 BTC, which I personally find very questionable.
Ofcourse they will. What else. Well some will other will pass like they don't hoard gold. Those that have lost of Gold now like Russia or Italy will for sure go big into Bitcoin.
But we are not there yet currently different financial institutions are buying Bitcoin. That was behind 2017 growth. Countries buying will be behind next bubble that might even not happen in this decade.