At transit layer to an extent yes, but with every underlying user of the connectivity considering the connection compromised, and therefore using their own meas

At transit layer to an extent yes, but with every underlying user of the connectivity considering the connection compromised, and therefore using their own measures on the untrusted link. Hence IPsec and site to site/road warrior VPN - the underlying connectivity is regarded as untrusted by any sane user. In telecoms, anyone on the SS7 network can make a request to find a given number, or say the number is available and can be reached by routing via their network.