This is key. You can't keep all of your data off the Internet, but you can guarantee nobody can see all of it by trying to prevent your various internet identities from being linked or associated, and keeping data siloed in different, disconnected services.

There's a couple things I do still use Google for, like YouTube. But since they no longer have 95% of my personal data, the impact of them having my YouTube history is drastically reduced.

Firstly, it is quite difficult to manage so many usernames and passwords, for non-tech-savvy people such as my parents.

Secondly, don't you think that actually maintaining it is very difficult? One inadvertant click could expose one of those accounts to another with a different service provider, etc. Arguably, it can work should you define a different browser profile for each of those accounts!? Nonetheless, it is neither easy nor smooth, in my opinion.