But faster than you can imagine, the next requirement comes in: OR filters!

    bicycles that are (made of steel AND weigh from 10 to 20kg) OR
    (made of carbon AND weigh from 5 to 10kg)

Hmm.. I don't know if this is a good example. I have been in the product search space for almost 10 years now and that feature request never came up. And I cataloged thousands of feature requests users had about product search interfaces.

In the rare case users do something like this, they usually use two tabs. One, where they compare steel bikes and one where they compare carbon bikes.

It makes sense, when you think about the frontend implications. Users are very used to checkboxes and range sliders. The user would check "steel" and set the range slider to "10-20". Now how do they expect to duplicate the sliders and the checkboxes to construct the alternative configuration? They open the page in a new tab and use the alternative settings in that tab.