"I think the easiest solution is log analytics, preferably from anonymized or pseudonymized logs that are present anyways."

"Maybe some (privacy-preserving) data can be added to the URL parameters to augment the logs and provide a little more insight."

Pathview iterates on the server log approach. JavaScript collects two pieces of information: the current page and the referring page. The rest of the data is acquired by parsing HTTP Messages in real-time.

The only difference is cloud vs. self-hosted.