There are far fewer people who have a contract that specifies that they will get a public IPv4 address on mobile.
On wired, just about every business account is assumed to have a public address and often a static one. In addition, a lot of gaming doesn't work behind carrier grade NAT.
In the mobile world, this expectation of public (or even static) IPv4 addresses is almost completely absent.
I don't see how this has anything to do with wired vs wireless.