These sound too obvious to be worth spending time on.
No-one sets out to be the opposite, and pretty much everyone would say they’re a good idea – so much so that you might feel foolish to stand up at a meeting and emphasise their importance.
But – and it’s a big but – a friendly and supportive atmosphere needs to be cultivated and protected, which means that it needs to be talked about.
Before that, they need to be defined and exemplified: “friendly” doesn’t mean “we accept all behaviours,” and “supportive” isn’t a license for persistent incompetence.
Once you’ve thought about what they mean for you and your team, all you have to do is live them. Simply that.