Bringing up an opinion poll as a counterpoint makes it read like you're arguing that Wikipedia should focus less on fact and more on opinion. Of course, you're free to think what you wish, but I suspect that's where most disagree.
Genetics certainly don't explain all the differences in IQ. They very well might not explain the majority of the the difference. However, considering we know that intelligence is quite heritable along with various adoption and twin studies that have happened throughout the decades (along with simple freaking logic), we have a pretty good idea that it explains at least some of the difference. That "opinion poll," while not super-great because only some elected to reply, was a poll of experts in the fields that study this stuff, not random people.
A real unbiased article would mention that (and perhaps whatever counterarguments there are), not straight up do the encyclopedia equivalent of sticking their fingers in their ears and going "nah uh I can't hear you."
"Anonymous surveys of intelligence experts reveal division: a 2016 survey found that about 49% attributed 50% or more of the Black-White gap to genetics, while over 80% attributed at least 20%; an earlier 1980s survey showed similar splits. These views are more common in private or anonymous contexts, contrasting with public statements from bodies like the APA that find no support for genetic explanations."
Hm, sure seems like Wikipedia should probably have a more balanced, nuanced discussion considering the experts are split at least 50/50.