The cloud is someone else's collection of computers operating at a very large scale. If my load changes in a way uncorrelated with other users', that's a very good thing. If my load is correlated with other users', that's may be bad. But it could still be good, because at that scale, they can justify having robust contingency plans -- back-up supply contracts, extra engineers around to ramp stuff up, or relatively unimportant stuff they can de-prioritize. (If you're relatively unimportant, that's a bummer; if you're a hospital getting priority, that's a plus.)

While true: only few individual companies would have enough computing power to handle their suddenly increasing load ready ... or capability to setup the services now in demand