S/MIME is still end to end encrypted. The fact that it relies on certificates means that it doesn’t protects against spoofing and one can argue that the certifi

S/MIME is still end to end encrypted. The fact that it relies on certificates means that it doesn’t protects against spoofing and one can argue that the certificate chain makes spoofing “easier” by creating an implicit chain of trust. However pretty much every E2EE protocol doesn’t addresses spoofing without a side channel exchange of some sort which would allow you to pin the key of the party you wish to communicate with.