That's a fair comment! I had this exact same discussion when I gave a workshop about it when some attendees.
No, I don't mean 'fake agreeableness'. A survey from RP showed that EAs scored lower in agreeableness compared to a sample of random American people (I think), and this makes sense when I see how a big part of the community interacts. People tend to be very data-oriented/sharp, which comes with good traits, but can also come across as unpleasant. There is a lack of social skills in the EA community--pin this to youth, pin this to evolving in a very intellectual environment where agreeableness isn't always put as a priority, but I've noticed that many times.
What I'm saying is put some effort in being agreeable, even if it doesn't come naturally. Not only because it helps tremendously in policymaking, but also because everybody benefits from it--you bond better, you connect better, and you pay attention to your interlocutor's body cues.
Creating a better environment is a win-win process for everybody involved, even if it means you putting more effort into this, which you would not usually do. Not only it makes EA more accessible and warm, which we need, but it also helps you, on a personal level, to interact with people, in and outside of EA.
Having worked on diversity within EA, I can safely say that putting intellect beyond being mindful and warm is unappealing and counterproductive. Which I why I titled my post 'soft-skills'. I think they're widely underrated, and I've heard many people say 'I don't need to be kind/warm when I'm working, what matters is the content'. The content only comes if it's packed under a pleasant cover, otherwise people dread doing business with you.
Your last point is to true. It's so replenishing to do that after a day of 1-1s.