The exchanges don't want (or pretend to ignore) the Know Your Customer (KYC) rules, which your brokerage does not.
So your brokerage is fine sending you the funds immediately. They also are fine with the audits, etc that are required to prove that they're not playing sillybuggers with your stocks or funds.
Just a side note, but it's funny how the Patriot Act is commonly decried by everyone as an overreach of government power & invasion of privacy.
But, when you mention these KYC laws (which were put into place in the US by the Patriot Act), no one bats an eye and just assumes KYC rules are reasonable.
The Patriot Act is a broad-ranging piece of legislation, and the anti-money laundering provisions in Title III are less controversial than other titles.
What is unreasonable about brokerages and crypto exchanges being subject to KYC and AML regulations? How is that at all comparable to the government being able to eavesdrop on my private communications and violate my 4th amendment rights without a warrant?
You can simultaneously believe that financial transactions are private communications, and also that a securities broker being required to verify their customer's identity pursuant to KYC and AML regulations is reasonable. Your post is very vague (since the comment you're giving thanks to focused on a semantics "gotcha" and completely avoided the actual point) so I'm curious as to why you think KYC/AML regulations are invalid and brokerages and centralized crypto exchanges shouldn't be subject to them in the light of "private financial transactions".
In fairness it took me about 2 months to withdraw from an "instant access" account around the new year, because my bank demanded documents that don't exist in the country I'm living in. They also refused to even stop paying me interest that creates a tax liability, so I'm going to have to file a tax return to report less than £2 of interest this year.
So your brokerage is fine sending you the funds immediately. They also are fine with the audits, etc that are required to prove that they're not playing sillybuggers with your stocks or funds.