Ok you say we just adapt? Cubecraft had about 15k players in the 1.8 era. What happened when Cubecraft almost dropped all support for 1.8, and just a few bigger ones? We are now on 4k players on avarage.
Secondly, 1.8 isn't unnecessary. There are 1.8 players who love this server. I've been here since 2013 and wouldn't want to leave for any other server. But, when this server becomes solely 1.9+, don't be surprised that a large part of the playerbase leaves. A lot of mods, helpers and the majority of the devs (sentinental) play on 1.8, so the server also takes a large hit. See what happened to mineplex when the devs split up.
And when you're running for president, you have to make everyone happy. If you just go for the people who would already vote for you, but they're just 10% of the country, you won't win. You have to get the majority of the people, even if you lose some that were on you're side previously.