That survey is stupid in this context, as it include everyone 18+ as an ‘adult child’, which includes a lot of college students. There’s nothing malicious about supporting your kid in college, nor would it make any sense to tax that.

Nothing wrong with giving money to your kids in general. That income has already been taxed. If they were paying the kids for pretend work and taking a deduction for the higher-income parents, that'd be different.