Tufts may seem to have a weaker reputation than Notre Dame because it is a relatively new addition to the circle of elite universities. 50 years ago, Tufts was considered a commuter school. My guess is that Notre Dame was ahead of Tufts in rep back then, so older people may know its name more often than Tufts. Tufts also wasn’t great with alumni engagement until more recently, so that could have something to do with alumni perception of their respective schools.
Notre Dame is much more of a traditional college experience; Tufts is more unconventional. I would also guess that Tufts is a good amount more liberal and has much more of an artsy vibe to it. I can’t specifically comment on the differences in engineering, but Tufts’s class of 2024 had more female than male students accepted to the engineering school this year (which likely means that there will be a roughly equivalent number of men and women in the engineering school). Tufts also has a 0% attrition rate in the school of engineering, which I think points to the quality of it. However, if your son were to transfer to arts & sciences, it’s super easy.
I personally feel a big connection to the city of Boston since I engage with it pretty often, both in a political and experiential sense.
“Culture that resonates with me.” I think this is the most important aspect of an undergraduate education, and it’s personally why I chose Tufts. There is always grad school to go to for the sake of prestige/reputation/networking (even though Tufts has built a great rep for itself in the past decade or two). Your undergraduate years are some of the most formative years of your life. I wouldn’t trade those for the reputation of a school.