KYB process differences between prop firms and retail brokers

Been looking at a few prop firms lately, specifically those offering real capital accounts versus just demo challenges. The onboarding process, particularly the KYB, seems to vary wildly. Some feel like a full-blown institutional client setup, which is fine given the capital involved, but others are oddly light. Anyone else notice this disparity and how it might impact the due diligence you perform on the firm itself? Seems like a red flag if they're not verifying things properly.