No, I wouldn't consider that at all definitive as a study, and the authors specifically note the following:
"This study is limited by the lack of a control group or active comparison clinical intervention that would provide a basis for making a stronger inference about how MBSR might modify the behavioral and neural bases of different types of emotion regulation."
So while MBSR may help some people, this tested one specific method and did not include a control group or test against any other treatment methods.
Now, I'm not suggesting that meditation - MBSR or other - can't be helpful for some people (possibly even the majority of people under certain conditions), but it certainly has not been studied enough to show clear benefits compared to other treatment methods.
"This study is limited by the lack of a control group or active comparison clinical intervention that would provide a basis for making a stronger inference about how MBSR might modify the behavioral and neural bases of different types of emotion regulation."
So while MBSR may help some people, this tested one specific method and did not include a control group or test against any other treatment methods.
Now, I'm not suggesting that meditation - MBSR or other - can't be helpful for some people (possibly even the majority of people under certain conditions), but it certainly has not been studied enough to show clear benefits compared to other treatment methods.