This is why multiple SCT entries are required. Could you subvert all of this with enough effort? Yes, and the same is true of dnssec. Any form of cryptographic validation is only as secure as the control of its private keys, but modern TLS is designed to require you to compromise at least 3 independent parties in the TLS ecosystem to provide a plausible fake. And at that point why not just get the browser vendor to push a fake update to the user that disables TLS validation entirely? You're either doing all validation yourself, or you're trusting someone. Modern TLS avoids you needing to place trust in any one organisation from the TLS perspective, which makes attacks on other infrastructure components much more appealing.

I'm sorry, but I'm declining to do that, because I recognize the message board conversational pattern where all the information you have about the subject is coming from comments rebutting you (this is apparent from things you've said already that fundamentally misapprehend how CT works), and, rather than acknowledging any of that information, you just use it as vocabulary for new misapprehensions.

Aside from what mjg59 said, it's clear you don't quite understand how CT works. Logs are stood up and then go through a fairly rigorous acceptance process by Google (and Apple) before finally being used. 'Used' in that a CA can then submit pre-certs to it and include the resulting SCTs in signed certificates, making them functional on Chrome/Apple platforms. Even the CA using the log generally takes some communication with the log operator to ensure the right set of roots are trusted for submitted pre-certs.

CT logs are used by CAs, not clients. A 'fake' log isn't a thing.

Because they don't have access to the private key material owned by the CT logs that the browsers trust when validating SCT data in the certificate.