I wasn't offended or taking it serious, I was going along with it.
I've just heard stuff like this over the years and it cracks me up when I hear it because sometimes we get judged based on geographical location without any experience with the city. While I don't suggest this, I've walked many areas of Boston all hours of the night alone. You begin to learn where not to deviate towards and/or what to avoid when things don't look right.
Sadly random acts of crime have increased in many areas. Thankfully I have less of a need to walk Boston late night alone, and, I do agree, any car can be a target for breaking in regardless if valuables are in sight or not.
It's rare I keep anything of value in my car. A cheap plastic shovel in the trunk and a snow brush in the backseat. Anything of value such as a recent purchase is usually brought home. The laptop is due to sometimes needing to bring it home after work without the ability to go straight home.
Boston is a nice city, and, like any major city, we have homelessness issues, drug issues, but we have historic areas, many nice restaurants, etc... We also have a highway that is the same thing 95/128, but yet, they are also different because then they separate. We have signs around Boston that are mis-marked which brings you to an out-of-the-way area you don't want go be in, and, to make it even more fun, a constant changing of detours to accommodate construction; therefore making each trip into Boston a wonderful experience.