Do you even read the posts you're replying to? Nowhere did I say I preferred closed platforms to email. I don't. I used the word "battle" in my previous comment for a reason. You're preaching to the choir.
> I get a photographer, video maker or someone working in fashion (I am sure there are other cases, I know those) using facebook or <x social tool> for business communication because it is trendy or it is more convenient
You know that's 99% of the world, right? You just described everybody but people who work in tech. How am I supposed to communicate with people who don't check their email?
> The first is based on a distributed, well defined (RFCs??), open protocols and formats.
Insecure open protocols and buggy formats. You know all emails travel in the open air, right? This was the primary reason I suggested we replace it, with a system that is secure, easy to use and that people can control.