Re: Limited address space UK? IoT?
"Edit: unless home NAT is fine but carrier grade NAT is struggling."
Home NAT is fine for the most part.
Home NAT behind ISP NAT is a piece of crap (been there done that. It's the norm across SE Asia and you'll see it in the UK if you use your phone as a gateway. Lots of things start breaking in odd ways)
Carrier Grade NAT is an unmitigated 40 foot high pile of dingo shit which manages to put your security at risk too. (if your NATed IP keeps changing but the remote site is still talking to the old address, then someone else is getting your data thrown at them. There are some interesting attack surfaces to be explored there)