But implementing end-to-end encryption is much harder than adding a cookie notification.

https://www.howtogeek.com/166507/why-most-web-services-dont-...

There's a few startups working on platforms to make adding E2E encryption easier, but I doubt the EU is planning to mandate everyone use their services.

The plan sounds nice from a distance (who in tech is anti-encryption?) but closer inspection reveals problems. All legislation can do is ban certain activities. You want to release a new dating app, or add a basic messaging feature to your Q&A site, and you're not a crypto expert with 3 months to spend adding E2E encryption? Should it be illegal for you to release your app without encryption?