To expand a bit on what all this means at local level.

Services design their own AML/KYC policies and risk management processes with the over-arching guidelines and statutory requirements in mind.  Conventional financial institutions tend to have extremely conservative risk assessment frameworks because they're at risk of fines in the hundreds of millions if they're found to be non-compliant.

The risk assessment/management procedures individual institutions use are developed by them.  They get to decide which customers and what transactions are "high risk" and can and do choose to cease providing services to high risk accounts rather than apply enhanced AML/KYC compliance procedures to those accounts.  They are under no legal obligation whatsoever to allow you to operate a high risk account and don't have to justify a refusal to do so (under some circumstances, they may even be prohibited from giving you a specific reason).

Compliance is a huge administrative burden for financial institutions and it's both cheaper and easier for them to dump accounts/customers who add to that burden.  They not only don't care if you take your business elsewhere, they actively want you to do so - they want your accounts to be someone else's headache.

When your financial institution refuses to process a transaction or closes your account, they are not telling you what to do with your money.  They don't actually give a fuck what you do with your money.  What they're doing is refusing to act as the middleman in transactions which expose them to potential liability.  Any fees they might have earned from that transaction pale into insignificance compared to the fines which allowing a single transaction which breaches AML/KYC requirements can attract (it's 11 million per breach here in Australia for a corporation and a single transaction can involve multiple breaches).  It's not about your right to send funds to potentially flaky Bitcoin services or Nigerian "princes" - it's about their right (and, to a large extent, obligation) to not involve themselves in high risk transactions.

People in general greatly over-estimate their importance as customers to financial institutions.  You may believe that you're giving them "a lot of business", but in the overall context of their operations you're not bringing them enough profit to justify the risks involved in servicing your account.  They can always find low risk customers to replace you.