A bit later in the article also addresses this:

That consent, [Zoom Chief Product Officer Smita] Hashim closed, still won’t allow third parties to train an AI off your calls: “And even if you chose to share your data, it will not be used for training of any third-party models.”

However, glancing through the ToS I don't see where Zoom prohibits third-party AI training, only prohibiting training their own models. On the other hand, data for training LLMs is apparently the modern gold-rush and it's feasible that Zoom wouldn't want that data to be accessed by any potential competitors.