I believe this to be a mistake. Quoting ZIP 1016:
For coinholder votes, a minimum of 420,000 ZEC (2% of the total eventual supply) MUST be voted, with a simple majority cast in favor, for a grant proposal to be approved.
If the votes for Abstain are removed from the tally (which is the only way to correctly interpret “Abstain” in a voting context), then this vote meets both the required threshold (1,140,324.875 non-abstaining votes were cast) and the simple majority (66.4% of non-abstaining votes).
The other votes all had sufficiently-large margins that (at a glance) the results should be the same whether or not abstentions are counted.