I agree, making it a blocker would be good to raise awareness about the danger of not knowing what they actually do with data.
However I believe a weight of 100 is too much, since it may be applied to services than simply did not take the time to verify all links or that don’t have any official and enforceable terms.
I would suggest a weight of 20 (currently the lower weight of a blocker is 30 for case-174 ) in order to avoid penalizing services that didn’t hire a lawyer to verify their terms.
If the service has a contact method that works, I agree. If they don’t offer one or it is broken (email bounces for instance, it’s happened to me before while reporting a ToS 404) then the strong penalty is deserved IMO.
Perhaps could we explain in the case’s description that it only applies to services that are impossible to contact to raise the issue, either because they don’t offer any contact method or they do not respond in a reasonable time?