Voting of shareholders of a company can still be called a democracy because the amount of shares – what's weighing the votes – is finite.
But the supply of .org domain names is effectively infinite, and so any "voting" weighed by domain names would just become a bidding contest.
There are only like 10 million .org domain names. At this rate it will cost just a bit more than $100 million to pass any decision requiring a simple majority, and a bit more if a supermajority is required. This is notably cheaper than the $1.3B acquisition price.
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If we want to entrench status quo, one solution is to require broad consensus of a sizeable but finite number of large players representing customers including the ones you mentioned.