I wouldn't say that Great Old One warlock abilities are inherently worse than Fiend warlock in tabletop, they are just completely different playstyles. I agree that several of their abilities and spells don't lend themselves to video games though.
However, with the set up of the game with mind flayers the narrative flavor potential is through the roof! I would like to see this subclass really lean into its psychic/alien roots and maybe even strengthen some of the characters tadpole abilities. They've already added "mortal reminder" instead of "awakened mind" at level one, so I'm sure they'll think of some interesting changes for the full release.
