You might not be thrilled about Medford, but you should be thrilled about Somerville/ Davis Square, which is REALLY the social hub for Tufts students. A great area with theater, shops, cafes, restaurants, clubs, and it’s a “Joey” hop or 10 minute walk from campus; easy peasy access to Cambridge and Boston. Somerville has the largest concentration of young people in the country, or something to that effect. Oh, and in a couple of years, there will be a direct-to-Boston line at the edge of the Tufts campus, from what I understand.
Not sure what you mean by “bubble”. If you mean socio-economic, it’s not something my D has noticed. Tufts is not a “showy” place, in that respect. It might have to do with the cause-oriented focus of the place.