Comment by bluGill
21 hours ago
There is nothing that makes sense. The world population is about twice the total number of IPv4 addresses total. Many people own more than one device, and there are good networking reasons that you want most of the possible addresses on any network segment unused. There is no way to solve all of those problems at the same time and so nothing make sense when we are talking about IPv4 and it never will.
NAT is the solution so far
NAT is a terrible solution with major downsides.
We are close to not having enough just for the servers people really want much less random things that should be contactable peer to peer.
NAT should not replace a firewall
Sure, but it's evidently not that bad. And actually safer than firewalls because the default is so strongly deny-inbound. Most people absolutely don't want random devices on LAN to be exposed to WAN, and those with servers can get a public IP.