Silver Line was part of the Big Dig, but I agree the North/South Rail Link should have been part of it. Having no direct connection between North Station and South Station is stupid.

But you can't just get rid of 93

You absolutely can just get rid of 93 within city limits, especially if 30 billion was spent on adding more commuter rail.

The idea that highways must cut through the city, especially one as geographically small as Boston, has been thoroughly debunked.