There's no incentive for migrating to ipv6 for corporations. I have said this previously NAT breaks the Internet [0]. Without setting an expiration date for ipv4 NAT is going to get dragged to 2050.

[0]:https://news.ycombinator.com/item?id=20253427

IPv6 significantly simplifies your internal numbering.

Inside a corporation you don't need to "dual stack" you can just go pure IPv6 wall-to-wall and now all your subnets are arbitrary size and have globally unique addresses. You use NAT64 at the edge to get to the parts of the world that are stuck on IPv4.

Several big organisations have done this, it's a big saving.

Ipv6 adoption is slowly creeping up, and if you were to put grandma's broadband on ipv6 only, she would still be able to use Facebook, Twitter, and all the other major big sites.

I'd say the day some ISP's stop provisioning ipv4 (especially for 'social networks only' plans) might be getting close.

There are incentives. Smaller for US and European corporations, higher for Indian ones.

Maybe NAT breaks the Internet of twenty years ago. But we've already worked around it. I'm using a computer which is behind a NAT which is behind a CG-NAT and everything works fine. Sure, people can't connect to me directly, but why would I want that to happen? If anything, that makes my computer more secure.

I know this sounds like trolling, but let's be pragmatic.

Some users do want people to be able to connect to them directly though, hence Universal Plug and Play (UPnP), which can open ports on your router. You may disagree with the wisdom of automating the port forwarding process for people who don't understand networking concepts but there are people that do want other people to be able to connect to them directly, even if you don't.

Generalizing that one use case will suits everybody, fits about as well as one-size-fits-all clothing. Which never fits right.

Those that want or need a public IP can pay for it. I do. As you say, there is no one-size-fits-all.

This is why we are stuck with huge corporations to provide services to connect to each other. We are sacrificing privacy because we don't want direct connections. We could have hosted an Instagram clone at home as well if NAT wasn't there.

Ability to connect directly does not necessarily mean that you are somehow more vulnerable to attack. There are measures that you can take to prevent attacks from happening. It's trivial to configure.