The short article is based on reading research by two people who did some kind of survey or study, rather than interacting with and knowing the stories of people. The first part is not about music, but about "participating in ensembles" and similar. In other words, if you engage in any group activity, you will meet other people who participate in that group activity. This is not specific to music. The second statement "concludes" that "music education" leads to a lower use of tobacco, alcohol, and drugs. Both are more about general, and rather casual extracurricular activities in a high school type environment (music and other hobbies and pursuits).
In a few ways, pursuing music is socially isolating, and not just as Bob stated, because of the time needed to practice alone. One reason I go to forums is because of the isolation. For most people I encounter or know in my environment, music doesn't go beyond "ooh, that's so pretty" or at most a passive appreciation of music. I am in a position of not being a professional to be able to play or sing at quite a professional level. Some years ago I joined a choir. Everyone else was there to socialize. I joined a better choir that required an audition and the ability to read music (but I was not tested on my reading ability - only if I could copy the piano). I was a fish out of water there too. In fact, it was a very lonely feeling.
In regards to the statement on alcohol, drugs etc. I have talked to people who studied music at advanced levels toward careers in conservatories and universities, and others who worked professionally in music. Quite a few reported that due to the pressures and stress, self-medication of various kinds is especially high in the arts. One decided against a career in music, and to pursue it as an "amateur" for enjoyment instead, because of what was seen as an unhealthy lifestyle.
I am not impressed by that article.