To borrow a phrase from Letterkenny: "Can confirm". I haven't seen any issue with 4k or 1080p videos in over a week now. Occasionally a video will take a few seconds to start streaming but that is definitely acceptable if it means the buffer is primed for a smooth experience after that point. I don't care if Rogers wants to try to save face by blaming Google or not at this point, although I don't really know why they bother with this type of pretense.
With the warm weather on the horizon I was literally a week or two away from calling Bell and doing some minor renovations to make their install acceptable.
Thanks again @AccordXTC