Dean is talking about including a Javascript snippet, but doesn't give any details.

Of course, what is sent by said snippet could probably be sent by other means, from PM's servers. Dean wouldn't get individual IP addresses, but for what he claims the project is about, that should not matter. Signs of activity and - MAYBE - the topic should be all that is needed to be useful to his project.

Between Matomo and Adobe's service, I'd be less distrustful of Matomo. Partly because it is (mostly) open source and partly because it's based in Europe. The CPAN modules Dean mentioned don't look useful for PM. Other than to note many integration "kits" on the website, I didn't dig into details.

As for potential benefit to PM, it might give PM more visibility.

Between increased visibility and avoiding privacy issues, I'd chose avoiding privacy issues. If Dean won't accept what PM is willing to share, then I'd say his project is not worth dealing with.

I am NOT saying PM should participate. Only offering my thoughts.