No it doesn't, it creates confusion.
The DM says "King Zog the Mighty was king of Cormyr in 1254 DR", and a smart ass player says "but it states in [obscure out of print FR publication] that Bloglov the Stupid was King in that year".
The official WotC position is that "canon" is whatever the DM of that game says is canon. Every game has it's own canon, and there is no super-canon that overrules that. The material WotC publish is just source material that DMs can use as is, use altered, or ignore completely.
If a DM is playing a Ravnica campaign, they are free to use the MotG cosmology, the D&D "Great Wheel" cosmology, or any other cosmology they like.