That was a display of the telemetry, so it indicated the actual status of the engines as far as I understand.

If they had intentionally disabled some engines, they would have mentioned that on the stream.

Yes. With 33 engines of a new design losing 1 or 2 would be pretty unremarkable and worth adding to the graphic. Losing 5 is getting into "needs improvement" and I'm sure SpaceX will be looking hard at the data they collected to see what about the design or ignition sequence they can improve next time.

I think it's astonishing the thing continued to fly after having parts of it explode and random engines seemed to shut off.

With the energies and margins involved staying in one piece through a failure is both amazing and critically important.

I'm curious about their launch cadence after this.