That’s a great idea! Check out the guild recruitment page over on https://eu.forums.blizzard.com/en/wow/c/recruitment/54 . It can’t be stressed enough that being nice, patient, and polite in the mythic groups will generate connections that can flourish into friendships.
While it does take a little effort to stay connected with these new people till a rapport is built and you start to do things together regularly, increasing your social circle is an excellent way to find like-minded folks to run with. You might even have real life friends who play that you didn’t even know about! Try announcing on your social media that you’re looking for buddies to roll with 
Maybe you’ll even find some folks you know who don’t play WoW (or game in general) who’re looking scratch that social itch. Be pro-active. It’s good to reach out!