As we have all found out, that trust is misplaced, as "cloud" services were systematically abused.In a way after Snowden revelations we all now need to learn Aesop language (slang is actually almost in-penetratable to computer analysis, unless they are specifically programmed for the particular one) and be more careful.And they become oligopolies because we agree to use them as primary sources, for example Google for search, independently whether it is good for all types of searches or not.
Using three engines you create a need to merge and correlate all three activities, which represent not an easy task, as in this case there is no guarantee that those activities represent actions of a single person or a group of persons (especially, if you use a local proxy).
When everyone using an Android smartphone is forced to wear Google's digital straitjacket.
This can be a very bad thing, and it make combination of a "regular phone" and a 7 inch tablet much more attractive then smartphone (and available a fraction of the cost).
And set of emails voluntarily stored by you on "cloud" provider (is not this stupid ?
) is the place over which you've absolutely no control (and as such ) . The ability to listen to your phone calls in most cases is immaterial.