Whilst I agree that they are paid to race, and are meant to be 'the best in the world', and I don't like the pansy, limp wristed attitude of most current F1 drivers, but...
...allow me to put my experience of single seaters. I have, in my car, less power, less downforce, smaller tyres and less skill. But if the rain is flooding the track to depths of several centimeters there is no way you can race. It doesn't take that much water until a car weighing half a tonne simply aquaplanes. And when that happens you can't accelerate, brake or steer - you continue in more or less a straight line at the speed you were going.
I've been there. I was lucky that I wasn't on a very fast bit of the track. But once you've aquaplaned in anything from a Formula Vee upto a Formula 1 then your bank balance, skill levels, experience etc have absolutely nothing to do with it.
And don't say they can just go even slower - surely you know that an F1 car needs to move to get cooling. Surely you know that with small groud clearances that the electronics would be swamped in seconds. Surely you realise that even in English rain you can't see a rain light on the car ahead (hint: onboard cameras allow the viewer approximately 200 - 500% better visibility in the wet in pretty much every series) until you've hit it.
So, for once, I agree with race control on this. The race HAD to be stopped. Anyone who disagrees is an ignorant fool.
Edit: And that's not taking into account the track side personnel that Keiran mentions.