I don't understand these arguments, really. It seems strange to me.
Breakdowns? Busses break down about 60% more than trolleys. Especially with the way the T maintains their bus fleet. And a 60 foot articulated bus will create even more of an obstruction than a broken down trolley. Plus, to move the broken bus out of the way, you'd have to fix it in place (it's too large to put on a tow truck!), and that takes time. Removing a broken trolley is a matter of minutes; the trolley behind it can push it out of the way. I've seen it happen a few times on the other surface lines.
Not to mention that in times of snow, busses are immediately disabled. Trolleys are not.
As for eliminating the parking spaces to create "suitable loading areas"... this is not a matter or Trolley transportation but a matter of the excessive safety regulations in this country. Why?! So many cities all over the world have trolley systems that are completely street-running, and no-one gets killed or injured getting off a trolley. Big deal, they're acting like people are gonna be forced to get off in the middle of a four-lane interstate highway... Come on. People are getting off and on just fine on the street-running portion of the E line. I say just restore the line to the way it was, without platforms for stations.