I'm not one of the people that has been concerned about that, but I'm curious to what extent this alleviates those concerns among those that have had them.
I am, it's mind-blowing to me that anyone would login to a search engine (yes, I know how many do it, now).
After a brief verification of the system, I'm pretty sure I'll sign up, now
I honestly feel like any major free search engine is probably doing more to try to track you anyway.
And if you’re going to search something you want to be anonymous, you can just like use another search engine. I honestly haven’t run into the situation where I needed to.
I do worry that some day someone will be able to see how often I forget basic syntax for some JavaScript or Python method - or how often I can’t be bothered to type out a full domain and just search to navigate to it - but that’s a price I’m also willing to pay.
Again, not sure on how the tokens are proven legit without ever sharing them, but there's probably some ~~zero-knowledge proof~~ stuff going on that covers that.
Edit: Not zero-knowledge proof. Seems to be Blind Signature?
It solves the problem of using a paid service without compromising customer’s privacy which is a breakthrough. The rest are different problems and they are universal issues with various existing solutions as you already pointed out.