Fuck ads.
You’re lying to yourself if you think ads will ever be delivered without tracking.
This whole “anonymization” nonsense is a lie. It’s been shown, repeatedly, that data can be de-anonymised, especially data that’s not exactly narrowly collected.
Have you solved the issues Syncthing has with Android? Seems Android v9 and later networking blocks the LAN access for finding local relays. Even manually configuring relay IPs in Syncthing doesn’t resolve the issue.