Actually the number of content creators has exceeded and to give upvotes to each of them is not possible as for the voting strength renewal mechanism of steemit is concerned. We know that, in 24 hours only 20% of the voting strength is replenished and casting vote at full deplets voting power by 2%. By that mechanism, a curator can only cast 10 votes in 24 hours. However curators have huge steem powe, r that's why they do not need to vote with full strength but still the number of content creators has increase d many fold . So it's not possible to guarantee upvotes.

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