Done KYC on six different exchanges this year, same documents every single time, different wait times every single time, there has to be a better way

Passport front and back. Selfie with passport. Proof of address. Sometimes a video. Sometimes a liveness check. Sometimes all of the above twice because the first submission got rejected for reasons nobody explained clearly.
Done this on six different exchanges this year. Every single one wants the same information. Every single one has a different interface, a different wait time, and a different way of telling you your submission is under review without giving you any indication of how long that actually means.
Fastest approval I got was 20 minutes. Slowest was 11 days. Both asked for identical documents.
I understand why KYC exists and I'm not arguing against compliance. What I don't understand is why there is no standardization, no portability, no way to say I've already verified my identity on platform X, can we just use that.
In every other area of tech we figured out single sign on, shared authentication, reusable credentials. Crypto KYC still works like it's 2009 and every company is building the same thing from scratch independently.
Is anyone actually solving this or are we all just going to keep uploading the same passport photo forever