A tsunami wave isn't necessarily high, it is not at all like a regular wave which arrives on shore, breaks and immediately dissipates. A tsunami wave could be just a handful of inches high but it keeps coming on and on and on, pushing more and more water in as the incoming rush of water seems to never stop.
It is why I don't think tidal wave is a bad term for the phenomena, A wave that comes in like the tide. at least as good as tsunami, literally harbor wave, Which I guess is a wave you get in a harbor(a place with no waves usually)
Tsunamic tide would be better - as it operates like a high tide, which can be relatively shallow but still cause a lot of action.
This could have been so much worse if a big tsunami was triggered though. Thankful the shaking didn't generate one