Mandatory body cams were also dismissed by the cynical, and it's the rule in many forces now, perhaps even most. This is just an extension of that policy.
No, it isn't actionable. It would require constitutional amendments in multiple states, changes to state law, changes to multiple federal laws, and I wouldn't be surprised if it all got thrown out at multiple levels. That is no more an action than "thoughts and prayers".
That requires a reliable test that can filter them, including new officers. If you think you can easily filter "good" and "bad" people, acting in extreme circumstances, you're delusional.
Mandatory body cams were also dismissed by the cynical, and it's the rule in many forces now, perhaps even most. This is just an extension of that policy.