I believe your frame of reference is a small environment. If all the stakeholders fit in the "2 pizza" team, regularly talk/meet, and regularly review progress

I believe your frame of reference is a small environment. If all the stakeholders fit in the "2 pizza" team, regularly talk/meet, and regularly review progress/ideas/etc. then sure, writing is irrelevant. Frankly, for me, reading is a far LOWER mental load than listening to someone talk. Talking is linear, and often stream of consciousness. I can't jump forwards to see if they are drawing the conclusion they seem to be aiming at, and if so, scan the rest for any variations. I can't jump back, without disrupting others, when they have made a cognitive leap that I didn't follow, to re-read to see if I missed anything. Often people aren't able to quickly order their thoughts, speak to these points, and stay on point/relevant in the face of q&a when it's a deep technical topic. I'd much rather read their perspective.