I don't really like Mr. Stamos because he has been saying everything he can to discredit Facebook since he got ejected after a row with management. This could just be my perception of him but I don't find his arguments to be entirely in good faith.

Denying E2EE is a cost as you are punishing people for the crimes of another, this is depriving them of their hard-earned freedoms and liberties, for something someone else has done or may do.

Look at the activism going on today. BLM, dissidents in China, the rise of oppressive far-right governments in Europe like Hungary. I am sure if you dig far enough, you could find many people fighting in obscure causes, high profile causes, in a number of countries, who would fear the fist of an oppressive government.

What if the FBI / NSA decides to surveil BLM, as they already are? What if the CCP strikes down a dissident as they already have on Zoom? What if Orban decides you are a secret agent of George Soros plotting to undermine the government? Is it the case that everyone should roll over because a criminal might use the same means as them?

There is also a cost in not having your smart TV microphone record all conversations and upload them to the police.

People who wish to mask their crimes have a greater incentive to use E2EE so will probably gravitate towards platforms that offer it. I would therefore suggest those not committing crimes are disproportionately affected by E2EE not being made the default where possible. Once one service in a particular category offers E2EE, the benefits of the other services in that category not offering it is significantly reduced.