It's extra work for website owners to build/test/maintain opt-out functionality. Have you considered offering a pre-built opt in/out widget which can be re-styled and integrated easily?
Or you could even just provide website owners with a "global opt-out" URL that they can stick in their footer.
We don't want anyone on the platform who isn't aware/comfortable with it. Our instructions to the websites (when they join) are to create a link to the opt out page. I supposed it could be a direct opt out
What do you mean? Unused cycles makes no sense. I'd be really annoyed if my laptop's battery life drops from 5 hours browsing the web to 1hour because it is running at 100% all the time due to this.
It isn't as much a matter of ability to verify, but to enforce. Currently the platform is supplied by quite a few websites (over 100), and the best way to get them to adequately communicate this is through proper incentives.
The incentives must be: if you do not comply, your content won't be monetized (as would happen with ads).