So it was revealed that addons will no longer be able to access chat logs or send messages. This has a big impact on non-combat related addons. MysticalOS (author of DBM) points this out as it will impact things like:
No Break Timers
No Note Sharing
No Keystone Info Sharing
No Durability/Buff checks
No Loot Addons (RCLootCouncil)
No Gamble Addons
No RP Timers
This seems like a big overstep in my opinion as these things are fairly important to most guilds and players. He suggests that they instead target combat event states instead of instances as a whole. Hopefully more attention can be brought to this and we can see some changes here.
Link to MysticalOS video: https://www.youtube.com/watch?v=RGcvWICMXWw