I wouldn't do a mailing list these days, but as someone who spent the early part of my career interacting with devs that preferred this method, it's actually pretty ergonomic by a 2005 standard. A message thread aware, text based email client that can turn messages into patches in a keystroke makes it actually pretty comparable to modern code review...
I think it's hard for younger devs to get this because they're used to email being stuck in a crappy, unthreaded browser interface or Outlook etc. (which are terrible for mailing lists) and most collaboration taking place in code review and chat platforms like Teams/Slack but for decades before these were feasible, email was the way...
I will watch this, but only because I'm fairly certain Neuromancer is unadaptable to the screen. The thing that makes William Gibson great is the fantastic way he writes, leaving so much to the imagination but creating a definite vibe. When you have to fill out every single detail to render it on screen, it's not going to be the same work. I'm sure It'll share characters and plot points, but these are not the things that make Neuromancer such a classic.