I believe his point isn't that every crime necessarily needs to go to trial, it's that we should have enough resources to be able to put every accused criminal

I believe his point isn't that every crime necessarily needs to go to trial, it's that we should have enough resources to be able to put every accused criminal to trial. The fact that it's not the case shows the significant disconnect in our legal system. That said, I don't believe it's very difficult to make an ethical and legal case against the concept of plea bargaining in the first place. I would argue it's very important to a free society to waste everyone's time proving that an accused person is guilty, and that not doing so violates the sixth amendment and fundamental human rights.