"Meetings are primarily for two things:" ... "Brainstorming" ..., ... "Making a decision as a group" ... "Secondary" ... "to expand and clarify knowledge"

I've said this before,

The "engineer's" pov on meetings is that they are an incredibly poor and overused instrument of getting things done and that it is beyond comprehension why "the company" continues to tolerate such expensive nonsense.

The manager's (current and aspiring) pov on meetings, especially physical presence meetings, is that they are the most effective way to reinforce the hierarchy/pecking order, sense allegiances and potential defectors, scout opportunities for ascension, or destabilize a rival in public.

You might call this 'cynical', but is it really when you lay out the facts?

As for the author's specific points:

Brainstorming in a meeting is by far the least effective way. It just comes down to the most brazen flaunting their unnuanced opinions in rapid fire while more considerate and intricate reasoning is speed ran and drowned out by loud advocacy.

"Group decisions", yes, to a point. Mostly needing 'formal' buy-in to CYA on a decision already made. "If you already knew this would be the (bad) outcome, why did you not speak up at the all hands meeting? Obviously you and everyone else supported this at the time".

"to expand and clarify knowledge": That is most often a lecture/presentation with Q&A attached, not a meeting