As a developer of a banking app, I do my best to avoid implementing this user-hostile crap, but not all developers are empowered to say "no" to this requirement and not all care. There is zero benefit to the user to block them from using your services, and I would argue the net benefit is negative to the service. Users aren't hacked via privilege escalation exploits, they are hacked by phishing, and they can be phished on a SafetyNet-compliant device just fine.
Thank you for being a smart banking app developer. There is so much bullshit in most of those apps that I consider them as "worst apps on my phone", but due to management incompetence rather than developer incompetence.