> IMO Google is doing the best they can to serve you relevant results

Maybe, but if so then they're singularly bad at it. Google consistently gives me worse results than DDG and Bing, anyway.

I really think it's because Google is trying to figure out what I "really mean" by my search queries, and it's really terrible at guessing.

What you really mean in a google search is you want to buy something. You only think you don't want to buy. It doesn't matter that you've lost the leaflet for your Pioneer 10 Subwoofer and want to remember which wire goes where in your new house. Or just want to remember some detail of something you had years ago. Google is there to assure you that you really want to buy a shiny new set.

Not buying stuff you already own again serves neither the economy nor Google's advertising profit. Go on, buy another set. Infinite growth depends on it.

That really is their attitude to every product and service.

I'm genuinely asking: can you share an example where the Google results are worse in your opinion than DDG or Bing? Ideally with a screenshot in case there is some personalization going on. I just want to see a very clear example of it so I can try it out for myself.

because you are being swamped by the order of magnitude more people that want to find a price or buy it.