Akthually, Betamax and betacam were completely unrelated standards. Betamax was the failed vhs competitor, with good quality but an unusably short recording length, and betacam was the unrelated standard that enjoyed a long and successful run in the professional world.
Technology connections has a few videos on the subject, but this one is probably the most relevant: https://youtu.be/hGVVAQVdEOs