I so much wish I had a cleanout. If I reached the step of demolishing the kitchen, I certainly would have installed a cleanout at that point, as well as a vent, and I would refuse to use tight 90° fittings (unless they have a long “swept” shape).
(edit) I have a main line cleanout, but there would be several splits & turns to make if i tried to use it to reach the kitchen. Might be possible if there exists a quite fancy snake that would have a cam on the end and a controllable bending mechanism. Not sure if such a tool even exists.