You want to support the ad-funded website you keep coming to, yes or no? Yeah ideally every website would have a paid option for the HN crowd with cushy jobs, but that's not always feasible.
In that case, ads, being psychological manipulation to get users to do things they would not otherwise do, are already highly unethical. The ethical think to do is to discourage their use, which includes blocking them for yourself thus making them less profitable overall.