You apply an arbitrary filter that deranks 'shitty' sites, and then you play a semantic game about what 'bias' is, and how you don't have it, but all the competing search engines do.
There's no objective measure of what site is 'good', and what site has been 'SEO-gamed' to rise to the top of <arbitrary search engine's algorithm>. The measures are subjective, and people complain when changes to the algorithm aimed at punishing black-hat-SEO also punish their website (Rightly or wrongly).
Not to mention the problem of using black-hat-SEO to punish a competitor (By creating scummy links to them, that make it look like they are trying to game the search engine.)
Growing up, my mother always used to give me books that contained content on page one. This goggle really brings back memories of wandering the dusty library isles of Mediterranean street markets with their pungent spices and beautifully crafted rugs.
I personally ? would remove SEO-bias by first exposing the actual construction of the site without SEO add-ons, to some engine for consideration. A simple example would be "built with wordpress". Please note that it is wise to know that I do not know, many many things. So it becomes a networked endeavor, to find and identify "literal attributes" to sites for the use of the engine, not my personal opinion of what the web-o-sphere is in 2022.
A very very significant example is the primary language group exposed on the site.. for example, Cantonese ? I personally support the rights of "minority" languages like Gaelic and Welsh in the European setting, Tamil for South Asia, things like that.. make it so..
I agree, the ability to reliably filter out overly-SEO sites, copy-spam, and other search engine-bait would be a true game changer! Defining and detecting it is of course the hard part.
The advantage that Brave and co have is that SEO sites will largely not be willing to make changes that decrease their Google rank to improve their Brave rank. If Google changes their algorithm, everyone will optimise for the new one, but as long as the Google algorithm is there and the main priority, Brave may be able to extract some useful signal.