Why answer the question at all? I use uBlock Origin's cosmetic filters to simply delete the prompt from the page. I nether accept nor decline, and I've never run into problems with this.
Have you ever tried booking flights with EasyJet? Their web servers would just literally stop sending you TCP packets once they see a session cookie that hasn't accepted the cookie consent within a minute or so. Took me a while to figure this out, and until I realised it's caused by me not seeing the cookie consent modal, my workflow was to clear cookies and then try to book the flight within 60 seconds. :-D
I've had no luck blocking YouTube's consent popup with uBlock Origin. From what I remember, it would randomize the element ID and also add a load delay, and if you managed to block it, it would block comments from loading or break scroll etc. With Consent-O-Matic, it works just fine.
Some websites block interaction until the pop-up is dismissed
In that case I usually just leave if it's not a site I absolutely have to use
As far as I've seen, they all do this using a transparent element placed over the page.. which I filter away.