I assume you mean NAT
Ok, I'll say it. So What.
My mum and dad for instance don't need a publicly visible IP, they would be MUCH safer without one, which is funnily enough why they run behind an old itx board running m0n0wall.
Many net users don't want or need a public address, why give it to them.
P2P is a bug bear of mine because most of the time its wholey inefficent (upstream at home is about 1.5mbit/s vrs 8 down) multicasting stuff makes more sense. Also don't get me started on the inherient flaws in BitTorrent protocol, clemidia, fix gear bikes, new labour and the daily mail are popular, that does not make either good or fun.
For times when its needed, the average family I'm talking here, I would have thought plenty of ISPs can NAT without too much overhead the users. It will also give them an ability to upsell which is quite important in the world of UK broadband providing.
So myself I don't care.
(should point out I have my class C still
)