As someone who is currently in a campaign using a GOO Warlock, I'm really hoping Awakened Mind is implemented in game in some form or another in the future. It just feels unfair to make the Great Old One get no Sub-Class Feat, while every other Sub-Class in game has their own Sub-Class Feats or Domain Spells available.
I know it may be difficult to work out an in-game implementation for Awakened Mind as a lot of the usefulness of Awakened Mind is in roleplay and not combat or in-game mechanics. Using telepathy as a form of secret team comms is really nice when I play in my campaign, but that wouldn't really translate into BG3. However, what I think is arguably the best use of the Awakened Mind's telepathy is rendered useless in how BG3 is currently implemented, and that is the fact that Language (apart from the odd "ghaik" and other non-Common words) seems to be totally absent from this game. If they implement languages in game in the future, then maybe telepathy would be of some use in BG3.
Otherwise, I think having an at will Detect Magic would at least give the GOO Warlock something. In a way I feel like they wrote themselves into a corner by just giving the player telepathy via tadpole, which in essence diminishes the impact Awakened Mind would have had in the game to begin with.