Ken Ham is a go-getter. Even with evolutionists shouting that he's wrong, he's sticking to his guns. Remember that the amount of people who believe something has no bearing on the truth of the claim. Even if one person believes in creationism, it could still be true. Likewise, even if everybody believes in evolution, it could still be wrong.
Lots of scientists back in the day were laughed at, ridiculed, and mocked for information we take for granted nowadays.