Let us take Draenei for example.
In TBC they retconned this entire race to give the Alliance a “monster-like” race that was still pretty or beautiful.
Did it cater towards people invested into the storyline? No.
Did it appease to people interested in the storyline? No.
It retconned a proportion of the existing lore all to appease people for the “looks” the race has.
Sure it worked short term, but long term, when you change existing lore for an easy satisfaction, it corrupts the foundation it was set upon. Because people will no longer get as invested if writers can just change stuff towards their liking on a whim, even worse if they do this for marketing purposes.
Take Blood Elves. Why would they ally themselves with the Horde? Because “it needed a pretty race”.
Kinda ironic that the Horde is now more popular than Alliance in Classic.
As with Vulpera. An Orc who encountered a Vulpera back in 2006 would literally try to eat it. I’ll leave it towards your own assumption on why they added this atrocity of a race with little to no background present in the Warcraft universe, despite them being made playable over races that are already well established into the storyline. (Ogres, Naga, Ethereals, Broken Draenei, Murlocs, Furbolgs)
I do think that the Warcraft universe has been taking massive hits because Blizzard does not care about being consistent anymore. They care about profit. They just create things inside the story that would be “easy to market”.
Imagine if Chris Metzen just wrote off the Orcs as evil. Because market wise, Orcs were an evil, savage, brutal trope in fantasy.
Blizzard is just too scared to be innovative on their story and lore, and are too scared to go outside their think box when it comes towards marketing.