Note, almost everything I'll write about here spoils the following video:
https://www.youtube.com/watch?v=T0Ydl82-0JU
So if you are curious on seeing how someone fares with the odds stacked up against them, like this without being spoiled, watch the video first.
Here's my conclusion: The game has an issue with reverse-difficulty-scaling and Brutal-AI just exacerbates this issue.
Surviving the first two months with it showed to be extremely difficult. It required a lot of skill, dedication and even a bit of luck.
The first goal is to extend the X-Com-project by not dropping too low in score twice in a row while getting what's necessary to get you to the mid-game.
In TFTD this means Ion-Armor. Ion-Armor made it so, that small-ufo-missions against non-lobsters became kinda trivial and secured a relatively stable income of score and stuff to sell while still looking a bit challenging. He tried to do a medium-landing site once but it was still too hard.
His new goal was Molecular-control. The ingredient necessary was a life Tasoth. He encountered them first on a cruise-ship-mission. And he got exactly what he came for. No chance to beat the mission but getting one life Tasoth was doable.
He didn't need to do anything difficult to stay afloat while getting his psi-training-facilities up and training his soldiers. All the score came from small subs. Bigger subs were ignored and terror-missions were just retreated from.
Molecular-control changed everything. Once he had a few decent psi-soldiers, it turned the game into a meme-fest and trivialized everything he did after that. The AI stopped mattering at that point. If they don't have control over their own units anymore, it makes no difference whether they would have acted smartly or not. He could beat a large lobsterman-sub fielding the nastiest of weapons without any losses. There's quite a lot of stuff to do to finish the game but I have a hard time imagining that anything could happen that could still stop him or even provide a reasonable challenge.
Sure, there were a few bloopers from the AI that he capitalized on and allowed him to get into this position. Most prominently the interaction of "There's 1 alien without a weapon spawned on Terror-Missions all the time" and "Brutal-AI will now try to pick up any weapon it can and is not limited how far it will go for this." This made getting the living Tasoth exceptionally easy as it was basically delivering itself for a juicy weapon he put out as a lure. Fixing the loadouts or changing the AI not to want to walk into danger they'd otherwise avoid to get one would have made it more difficult.
But I feel that any further improvements of the AI just make the discrepancy between extremely difficult early-game and mind-numbingly-easy mind-control late-game even bigger.
I'm now thinking of making a mod that turns the psi-item into something that just gives you a passive bonus to the stats that make mind-controlling you more difficult instead of giving that super-OP-ability to yourself.