Right now, whenever anyone groups up for a meeting, MS Teams, Slack, Zoom, whatever, it's usually an overwhelming experience. A live conversation hits every sense at once: you're reading tone, faces, and reactions, all while thinking on the spot. That makes it genuinely hard, especially as a first touchpoint, to get your ducks in a row, cover your corners, and get things right the first time.
In my opinion, and based on my experience, negative and positive, everyone needs some sort of pre-exposure to the topic before the meeting. A hardened outline, written down, so the whole thing can be audited, and so everyone has a resource to go back to.
Because when it comes to auditing: anything touching product requirements, you always, always, always want a paper trail. And when real money is involved, people have their rights, and people do not like it when their rights get violated.
So asynchronous communication is key. Those are the primary reasons why.