I can accept there being opposing views between Riker and Picard on what to do. I can even buy there being some anger in the mix. But the one thing that completely makes it out of character is Riker publicly telling Picard, "You just killed us all."
That was phenomenally over the top, not just in the fact he did say it but in front of the whole bridge crew... never mind the fact it was Riker who gave the order, and the responsibility ultimately falls on him. Riker was never one to shift responsibility or blame to someone else for his actions or orders.
Someone mentioned earlier in this thread that it's looking like our heroes are being deconstructed. They are right. (I think the wording was something like the current era of characters are not people we want to aspire to be, only people we wouldn't necessatily want to be around.)
I hope this is only very temporary because Beverly has already been damaged beyond repair.