Oh yeah, definitely. I'd rather commute 90 minutes on the train than in a car or bus. But 90 minutes commuting each way is still 3 hours per day spent commuting. It's certainly more palatable than driving, but I don't think it's appealing enough to have an outsized impact on the the city in terms of attracting a ton of Boston commuters. The people it'll appeal to are the people who already do the commute (there are good number of them), and a handful of people who work hybrid schedules only requiring a few days per week in the office and/or people who can work on the train and count those 3 hours as part of their work day. It's a fairly small group. If the trip time were 50-60 minutes, the appeal would be a good deal broader.It takes 90 minutes to drive from NB to Boston if you're lucky, and that's not even counting parking.
FWIW, I lived in Dartmouth for several years and did the Dartmouth-Boston commute. No matter how I tried to make it better (taking the bus from New Bedford, driving to Quincy for the Red Line, driving to Middleborough/Lakeville and Commuter Rail, carpooling, van share, etc.), it was not worth it. Not even for the lower cost of living. SCR would have been an improvement and easily the preferred method, but it's still a loooong day.