1. The tadpole makes it easy to form a party for a common goal, it even seems as if this was one of its main intentions
2. The mindflayers are very clever
3. This is all leading somewhere
So, since theorizing is allowed here: what if we're being tricked and played by the mindflayers into doing what we are currently doing? What if everything we do now is part of their masterplan?
Thats my fan theory for now.
Turn it around.
The Mindflayers are only interested in their own survival.
They dont like Magic, so obviously they want to fight such abominations like their t(h)ampered tadpoles.
Either the Mindflayers are enslaved by something else stronger then therir hivemind or they are somehow entangled in a conspiracy of epic proportions and have to do someones else bidding or be exterminated.
Or
Theres a renegade Mindflayer group trying to change they way of Mindflayer society.
Similar to the Mindflayer Omeluum who was born with the abilitiy to learn magic. (have to guess here if hes more like a wizard or sorcerer as a mindflayer???)
Probably its a much bigger story and several factions in the game try to seize the right moment for the powergrab.
I am really excited about what it will be in the end. If theres just only one power behind it, like a puppetmaster playing all those strings.