This exactly. And it's all because of the prequels. Before they came out, it seems like most of the Sith Lords in the EU were not Darths. They had names like Naga Sadow, Exar Kun, Ulic-Qel Droma, Marka Ragnos, Tulak Hord, and Freedon Nadd. Then Lucas came out with Darth Sidious and Darth Maul and suddenly the idea that Darth was a title and not Vader's first name became prevalent throughout Star Wars canon.
BioWare greatly added to this with KOTOR. And the lore hasn't been the same since. I've always maintained that the title Darth should only be reserved for the leader of the Sith Order, such as the Emperor and his Wrath. Everyone else would be Lords.
By having so many Darths running around it completely dilutes the effect of seeing one. A Darth is the face of darkness in Star Wars and the main evil - The Enemy so to speak. But now it's just a title that basically just means "General".
That is ironic in a way, since the Emperor was never actually a Darth but rather given the title of Lord by Marka Ragnos. After the end of the Great Hyperspace War, he just appointed himself as the Emperor, following his ritual on Nathema.
Also, it should
be pointed out that former Dark Lords, such as Naga Sadow or Marka Ragnos, didn't exactly agreed on that, so much that Gnost-Dural mentions it in one of his diaries...
Shame it's never actually further explored and / or expanded in the actual game.