Some are calling out workout fads such as SoulCycle and CrossFit as cult-like. This article also suggests that they are providing a connection to something bigger for some individuals. A role that was once reserved mostly for church-like environments, now may be filled by engaging with a company that provides community, along with something else, such as a great workout.
I think triathlon is providing this same community for many people. It is not as centralized as a specific company, but rather a bunch of communities that have arisen to support people in triathlon such as tri clubs, masters swimming groups, and online communities that support eachother in training, gear selection, etc. It is also unique enough that simply doing triathlons can connect you to the the broader community of other people participating in triathlon.
In a culture that is ,somehow becoming more individualized, where many people report not having any friends (a study found that about 20% of millennials report having no friends), it’s good to see communities designed around healthy activity, that also means getting outside and interacting in real time with other individuals.