Bullshit.
Firstly the cert revocation check does work.
You are assuming an arbitrarily advanced adversary who is assumed to pull both an MITM and also attempt to block access to the CA's servers. When in reality that may very well not be the case. Just because someone is doing an MITM does not mean that they will also block access to the CA's servers.
Secondly the MITM can happen at different levels. If the server that is sending you the response is being MITM'd but you are not, then you can safely access CA's servers and check for revocation. The MITM does not necessarily affect the client in a manner as to guarantee the failure to access the CA's servers.
And finally these personal attacks and Steve Gibson bashing really gets old.
Perhaps he made some mistakes or took controversial positions like ... when? 10 years ago? and people wont let it go.
The exclamation points and all caps and colored text and the ugly web pages is just his utilitarian and old-school style.
I listen to his weekly Security Now podcast and without failure he is well-prepared, thorough, accurate and correct. Even when he makes a small mistake next week he comes along, specifies the exact mistake and apologises and corrects it.
Instead every time he is mentioned someone comes along and says "ew hurr durr 10 years ago he said something about raw sockets in XP".
My point is, no one is perfect, and he certainly has not done anything to deserve these personal bashings and attacks from the community, if anything he is a long-time contributor, has put many tools available online and is now developing the SQRL login systems in the public ... so ... give him a break.