I wanted to further clarify my “They left Mystic Falls in the hands of Matt Donovan and expected it to turn out well” comment.
Matt Donovan has the incredibly difficult task of being the only remaining pure and innocent character on The Vampire Diaries. This distinction comes at a cost.
Yes, I did intend for it to be funny, but I was also serious. Matt Donovan has spent 6 seasons trying to distance himself from vampires, while at the same time trying to eliminate them when he thought it was necessary.
By virtue of attempting to distance himself from the supernatural, he distanced himself from any and all crucial knowledge that would have aided him in his attempts to eliminate supernatural threats. This is why, more often than not, he ended up getting in the way or getting himself or someone else injured in his good-natured attempts to help.
Because of this, Matt Donovan has arguably the littlest amount of knowledge of all the main characters when it comes to fighting vampires and werewolves. Therefore, he is not the best person to be put in charge of safeguarding an entire town against an attack from a group of vampire/witch hybrids.
But Elena is out of the picture, Jeremy has no doubt left to go be a vampire hunter elsewhere, Alaric is mourning the loss of his fiancé and their unborn children, Damon is probably useless without Elena, Stefan and Caroline have a whole slew of their own problems to deal with, and Bonnie will be busy both hating herself for being the one person who can bring Elena back, and trying (and failing) to keep her friends together.
So that is what I meant. Matt means well (as always), but is ill-equipped for what is coming.