OP is just suggesting you vote with your 'wallet' by not using those sites - they're not saying you should stop complaining.

Bad actors generally win monitary contests. The entire vote with your wallet is a mostly disproven idea.

it merely points out the hypocrisy of those who complain, but continue to use said sites.

Is unethical the right word?

Unpleasant might fit better.

It doesn't break ethical rules to ensure ads are shown so income can be generated to pay for hosting.

There are many ways to pay for hosting. Ads are just one way. Since they have proven so lucrative for some well positioned businesses, those businesses have pushed the meme that the only choices are ads or paid subscription. There are other ways. I’ve run sites where I happily paid the hosting bill because I correctly suspected it would lead to me getting the job I wanted down the road. You could say that sounds like advertising, but it was not run as a business, much less an advertising business. There was no self promotion whatsoever other than bragging rights.

Many people have agendas, including sometimes very positive agendas, that lead them to support online services of various types in order to further those agendas.

None of this is to say there’s no place for advertising or for paid subscriptions. I’m just saying there are often more options.

Ads, fine. Participating into a pervasive tracking infrastructure that strips you bare of your privacy to optimize manipulation of your individual cognitive faults is entirely another thing.