Yes, Residential ISP's can sell or lease their space to AWS, etc. for example and just start moving their customers over to CGNAT. Why bother upgrading your entire network, planning allocations, etc when you can just NAT everyone for cheap?
Can confirm this is happening. If you're lucky enough to have a choice in ISP, there are a few that won't CGNAT you. I pay a little extra for this ($10 a month) but it's worth it for me. Ask your ISP if that sounds interesting.
Is that really a feasible long term solution though? I require port forwarding and also work from home so require my service not get blocked due to some spammer on my block.
This honestly sounds like a perfect case for a business connection. Not only does it give you a static IP without NAT, possibly in an address block with other high paying (==reputable) people, it also bumps you up a lot in terms of customer service and service availability. Usually the first two questions in an outage are "how many customers are offline, and are any business connections impacted".
That assumes the ISP is willing to run a business connection to a residential address. Not every ISP will, especially if you're just a home user with special requirements and not an actual business.
Yes, but it doesn’t require upgrading all your routing hardware and the planning involved with adapting your physical network design to work with the hierarchical structure of IPv6 (we’ve had TCAM large enough to map every /24 of the v4 space for some time now, you can’t get away with that shit with v6 even if your hardware optimizes TCAM usage for routes up to /64’s).
This is why many residential ISPs and business haven’t implemented IPv6 yet (well, the later enjoys the false sense of security NAT provides too).
However, I also have native ipv6 to the home for as many devices as I want. It's easy to forget that carrier NAT is expensive for ISPs as NAT hardware needs a lot of fast RAM.