CLI is not signalling info
A lot of countries can't/don't/won't supply CLI last I heard
CLI is a presentation service, it's the number you want to have displayed to the recipient. It's completely unrelated to the actual calling number, which has to be provided in the signalling messages so that that the call can be billed.
Whether someone provides valid CLI or not isn't important, the telcos can use the real data which will always be there, and they can/should discard calls where that is demonstrably false, such as a call coming from India claiming to be from the UK.
The standards you point to are for the very last leg, from your exchange to your phone. They explain why a US phone won't display CLID when connected to a UK exchange line, but they have no relation to the actual data transmission across the network, which is handled by SS7 ISUP packets.
Biting the hand that feeds IT
