Surely that depends on where in Asia you're looking at as well? On average, the number of languages people speak is quite different between, say, India and Japan. Or Switzerland vs Romania in Europe.

As an asian, this has been my experience as well. Of course there are exceptions, but most asians I know (not just in my country) usually just speak 2 languages.

I think it also really depends where you are, which is why generalising entire continents maybe isn't very useful. Someone from Luxemburg or somewhere in the Netherlands with more recent immigrants is going to be a lot more likely to speak multiple languages than say someone from Russia or more rural France, just as someone from China is more often going to be monolingual compared to someone from India or Singapore

"Hey let me just make a quick generalization about like three billion people".