Singular, open, surveys online, are rarely good data. This suggests there are a lot of people, in comparison to the general population, who do not identify as definitely CIS, and presents some interesting things to think about. However, the actual scientific value of this survey is pretty poor. Online surveys are particularly bad for academic considerations, especially when there is just one.
Dude is being a dick though. However saying you doubt the veracity of a single online survey isn't a clear sign of bigotry. There are many reasons to doubt ANY online survey. If you would like to find out why, you can search something like "are online surveys particularly bad for scientific research", and you will get a lot of work discussing why this is so.
You keep repeating your really faulty logic. Repeating bullshit doesn't make it true.