Resposive ads doesn’t bring much revenue.
Well I use responsive ads exclusively and my revenue is better than what you report by a good margin, mind you revenue may not the be the best measure as it heavily dependent on your niche.
You can look into creative sizes from reports section of Adsense report, to see which ad size performs well.
Unfortunately it is not that simple, for example when I look at my report all I see is how great my responsive ads are performing, but I cannot see how much better the non-responsive ads that I did not use would have performed. You could show responsive ads on some pages and non-responsive on others, but again ad performance tends to be page dependent, so the result may not be accurate. The only way to test it, would be using an A-B test. Unfortunately Adsense removed the ability to A-B test any ads other that Auto-Ads. So you would need to set that up yourself.
If adsense is a game of supply and demand, websites which got most ads should win, it doesn’t.
I'm not sure I understand that statement, but the volume of ad-fills is not a measure of success, in fact one needs to be performing pretty badly to get low fill rates, because there are always advertisers willing to buy un-filled inventory on the cheap. See the comments about ear-wax ads earlier in this thread, as proof of this.
AdSense works by auction, your impressions consist of your inventory (not the number of pages of your website), that is the supply. Ad buyers bidding on your impressions are the demand. Getting buyers to increase their bids for your impression is "success". If there are only 10 buyers and you have only 1 impression, those buyers are likely willing to pay a lot for that impression maybe 10$ for a click, whereas if you suddenly have 10 impressions, then those 10 buyers can bid a penny and get filled, that is supply and demand.
Now if you have that 1 impression but you limit the ads that can appear to non-responsive, then there may only be one or two bidders willing to buy those ads, you have restricted demand and thus you will likely get a much lower price for that impression.
My example is over simplified, because your impression is 1 of millions of simultaneous impressions, and buyers are likely willing to keep buying impression as they become available, but the dynamics remain the same.
Restricting demand lowers prices.
Blocking ear-wax ads, is restricting demand and thus lowers prices, but there are situations when taking a lower price is beneficial in the long run. If users see spammy ads on your site, then they are not likely going to return, this will lower impressions and restrict your supply and lower your revenue.
The key is understanding dynamics of the market that you are operating in, such that you can make an informed decision as to what is right for your specific situation. If you have the means and the volume to warrant it, you can always A-B test to make the best choice, but I think for most us this will likely cost more than it will return.