I don't think you can say, "hindsight," when the mitigation was actually recommended in reports that were made before the event. It's only hindsight when mitigations become obvious after a disaster.
It's only really possible to make a determination about whether it was hindsight or not after seeing the prominence of the recommendation. Suppose I tell someone a thousand times, "you should wear seatbelts," and once to fix their taillight. Then they are killed in an accident after being flung from a vehicle while not wearing a seatbelt. It would not be hindsight for me to say, "they probably should have worn a seatbelt." Maybe it would be if they were killed in a freak accident involving an unfixed taillight.
Unfortunately, given I have only second-hand knowledge of these reports' existence, and given they are probably not in my native tongue, I'm not really in a position to validate what the situation was vis a vis the generators. However, generators positioned on the coast, behind a low seawall, in a country that is regularly inundated by tsunamis, appears to be an entirely predictable failure mode. Not quite to the degree of not bringing a parachute on a skydive, but in that direction.
I agree, I think that the language barrier is not a problem when you see those generators sitting right behind the seawall.
It's like in New Orleans, where the emergency generators were located in the basements below sea level. There's nothing subtle about that. Sorry, but how daft can one get?