I have always been the hc/mything raider and was focused on PvE only.
The only reward that was unique for mythic raiders have always been mythic-only mounts. However, Blizz was never removing the mounts after the raid tier is over so anyone could get them in the next expansion if they were lucky enough.
Now, since they add special event that massively increases the drop rate of all those mounts, their rarity will fade more and more.
In the past I was a little sad that PvE players can;t get anything unique that will not be obtainable in the future but over the years I changed my mind and realised that making other people happy won’t make my life worse so I have nothing against this greedy emissary event.
However, on the other hand, we have PvP players who also get special mount every single season. The difference is that those mounts are removed from the game as soon as season ends and they are never added back to the game.
I honestly think that now, since we do not care about FOMO stuff anymore, it is the best time to add the ways to get all Glatiator mounts from the past again.