I think OP is overstating the significance of the survey. I'm sure it was intended as a bit of fun rather than as a serious, empirical study (the 'One...barely. I'm struggling' category tells us that, unless we're genuinely expecting a number of respondents who have Specific Language Impairment, for example).
If you are talking about countries like Denmark, the Netherlands, Sweden, Belgium or Norway, then yes. If you are talking about Asia, South America or Africa, then no.
It's not at all uncommon to meet people from Asia (e.g. India) or Africa (e.g. DRC) who have a degree of fluency (whatever that means) in at least three languages. Many Indians, for example, speak at least one regional language, plus Hindi and English. Many Africans also speak their country's national language, their own regional/tribal language, plus other (contact) languages. Multilingualism is the norm in many parts of the world, as has already been indicated above.