Look, there are not a lot of great polls about people's opinion on whether sex and gender are different. PRRI has a poll on general support for trans people (https://www.prri.org/research/americas-growing-support-for-t...), which suggests that 62% of Americans support letting trans people serve in the military and a plurality oppose bathroom bills. It also shows that a majority of Americans believe that there are only two genders, but only 43% of Americans believe that "strongly," and of course you could believe that sex and gender are different while also believing in only two genders. I don't see clear proof one way or another, but this poll suggests that probably about half of Americans believe that gender can differ from sex. (I'll admit that for non-Americans, it's probably much lower.)
Look, there are not a lot of great polls about people's opinion on whether sex and gender are different. PRRI has a poll on general support for trans people (https://www.prri.org/research/americas-growing-support-for-t...), which suggests that 62% of Americans support letting trans people serve in the military and a plurality oppose bathroom bills. It also shows that a majority of Americans believe that there are only two genders, but only 43% of Americans believe that "strongly," and of course you could believe that sex and gender are different while also believing in only two genders. I don't see clear proof one way or another, but this poll suggests that probably about half of Americans believe that gender can differ from sex. (I'll admit that for non-Americans, it's probably much lower.)