It’s a cost thing: they should have added a couple more lanes to these roads 10+ years ago.
Part of route 93 north of Boston has it, southbound in the morning, northbound in the afternoon. Also part of route 128, south of mass pike. It’s clearly marked, only during posted rush hours. There are extra pull out areas added outside the breakdown lane.
Route 3 (north of 128) used to be only two lanes, was widened to 4+ lanes about 10 years ago. never had legal driving in breakdown lane.