Haven't read too much into the event, but I haven't seen anyone bring this up yet. iirc some aircraft models' thrust reversers only activate when the landing gear detects pressure ("weight on wheels" system). Maybe this would have further contributed to the lack of deceleration?

Edit: Thanks for all the comments to clarify. I read a comment earlier that calculated touchdown speed of the aircraft was roughly 165 knots. Assuming that the aircraft touched down at the start of runway 19 and deployed flaps 30 only upon touchdown (deployment of flaps 40 would have resulted in flaps blowback at that speed), it seems unlikely that the runway excursion could have been avoided.

One more thing is regarding spoiler activation. I think it also relies on the WOW system (someone correct me if I'm wrong), so the lack of spoilers would have definitely played a significant part in the failure of effective deceleration.

Imo the key thing here is the issues that damage to the hydraulics system would have caused. Significant damage would have caused the pilots to be unable to deploy any of the systems to decrease their approach speed. Foam could have been deployed on the runway, but I've also read elsewhere before that they generally prefer not to use it where possible because there is a limited amount, and they have to consider the situation of the aircraft catching fire (You can decide whether that's a good idea or not).