I have to confess, it's a guilty pleasure of mine to respond with a variant of the Nightmare GDPR letter to SOME companies who sent me the classic "we're sure that you want to access all the amazing benefits of our data processing so if you REALLY want to opt-out you'll need to click on this link and manually remove consent from a couple hundred 3rd party providers" email.
I'd never do that to any company (big or small) with whom I have legitimately interacted, but a lot of this drivel has come from random recruitment companies that must have scraped my details from my CV or Linkedin or wherever.