Discord is a concern, and other centrally controlled platforms are as well. That's why we're no longer on Twitch, and we've never considered YouTube or Facebook, even though it's been suggested numerous times.
We have other chats available at this time that work in conjunction with Discord, such as the Vimm chat, and steem.chat, which allow users who don't want to be on Discord to chat with the show hosts. The steem.chat bridge is really nice, since it allows users to see what's happening on Discord as well.
As it is right now, Discord is a big part of what we do, but we're not dependent on it as a means for interaction and live shows. It wouldn't be pleasant to lose it, but it's a thought that has crossed our mind.