I think they know much more than they are showing in that dashboard. Simply staying a few steps ahead and not giving them the option to even link to your account is worth for me.

To give an example on desktop, even using separate Firefox profiles for Google and non-google activity, it is embarrassingly easy to see that the activity comes from the same person. Just cross-check the bonanza of information like screen size, plugins, fonts etc. I would be surprised if they didn't do it. I prefer to not run the risk. So I go to even greater lengths than I mentioned above, however it was getting long.

To come back to your point, it's inconvenient only in the beginning to document yourself and to set it up. Whether it is rooting the device, or setting up your own e-mail server. In the end it is about the freedom of computing whatever you want on the device that you own.

EDIT: If I may add, it's not like I'm going full Stallman. Everything is a compromise, it would be nice if we weren't forced to go to these lengths, or to compromise at all.