The bounties look like they have fairly comparable distribution, and just knowing the dollar figures doesn't really tell much about either supply or demand. Your inference requires that knowledge.
Pricing of 0-days has very little correlation with the security of something, if any correlation.
I'm not sure what the "and for more" you are referencing. The site lists prices, an FAQ, and events. None of that supports the argument made by parent comment.
The number of public bounties for a system seems orthogonal to the number of actual vulnerabilities in a system. Of course, vulnerabilities exist independent of the existence of a bounty for them.
Don't pay attention to Samsung though, that company is probably the Apple equivalent of android.
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