It is great Tech. Very efficient.
But it is also a fare weather craft They can not operate in rough weather.
Heavy seas will either drown the engines or wreck the propellers. Since the craft depends on ground effect for lift they can’t climb above the weather.
That’s what I was thinking. This lumbering hulk might be impressive over a plate-flat inland lake, but put it in a choppy sea and watch it drown like a drunk goose.
IIRC, the Russians had problems with this design due to pilot fatigue - the combination of speed and surface-skimming altitude makes it tough to remain vigilant and spot threats - rogue waves, off-course fishing trawlers - things like that. Can’t climb over them, gotta swerve left or right - and that beast wasn’t terribly agile.