Yeah I have an issue with my PC being only of average intelligence. However, if there will be rolling I assume that I can just roll to get 2-3 more stats, so that is fine.
I agree that the issue with save-scumming is that it is a result of perceived failure. However I do not see how Larian breaks that up. If I succeed a check I am rather content with the result, if I fail I often have to face severe consequences and some checks are extremely hard to pass, too, even if your stats are good. Like when they make you pass two skillchecks in a row for the same result.
I don't mind average, just dislike playing an imbecile when this hasn't been fleshed-out in roleplaying games since early days of Fallout.
I might remember this wrong, but I got the impression than Larian has even provided some "red herring" options that are worded in a way that should and does make the check harder - even accounting for someone using that option with their best skill. So always defaulting to your best skill/ability might not always be your best option.
We are conditioned to think of success as the only acceptable outcome, both by binary design and likely by a bit of a hero complex that these types of games promote. I believed the example I mentioned about the illithid sucking your brain dry "break that up". Let me break that down for you in more detail:
1. Chance to kill illithid even before conversation, you are given loads of clues as to what is going on and don't need to put your arm into the crocodile's mouth so to speak. Most people do of course because they are used to being cuddled even against their own stupidity. Like jumping down the gaping black hole w/o Feather Fall and arriving dead on the scene in Underdark (statistics revealed over 40% of players did this). Gravity can be a bitch lol.
2. Chance to succeed multiple checks to avoid "perceived failure".
3. Even with what would be "catastrophic failure"/game over in any other game, you are instead rewarded with a challenging and interesting combat, and experience you don't otherwise get.
This game design is the staple of the game (though there are certainly exceptions as there should be), but I suspect you being so triggered by perceived failure means a hefty amount of confirmation bias on your part. All the other mechanics also work to limit the bad-RNG, several companions who can be used and built to limit any weaknesses etc, etc.
I would suggest there probably will be implemented a difficulty setting with optional easier skill checks, but I suspect your ego couldn't live with playing at lower difficulties too...am I rite?

Oh no, I do find the game too hard for me at the moment and would especially want the number of enemies to be turned down, my ego would be a bit hurt, but I would put it on easy. Although I have no issues with checks in combat, I know my statistics, it seems fair. However since I know stats skillchechks in dialogue are sometimes incredibly hard to master, since they require multiple skillchecks for the same goal. Take Nettie, depending on the dialogue, for the non-combat, good solution, you might have to pass 2-3 checks. One athletic for evading the thorn (which is fine, since it is a different issue) and two persuasion/intimidation checks for convincing her to give you the antidote, so for the same thing. And you might get +4 on every check, it does not have as much as an effect on the outcome as having two checks: 0.75 x 0.75 only equals a 56% chance. Add the third check and it comes down to 42%. That is with high bonuses and only for achieving one thing. With no bonuses whatsoever your chances drop to 25-12,5%
I agree though that the failure should be perceived as acceptable, or even rewarding, many systems do that now. Technically the Nettie situation does that, too, but it is a prime example of Larian offering a lot, yet not telling the player about it. The writing of the dialogue is not very good, so you do not really know what you are getting yourself into. At the same time only the good option (difficult to pull off, due to checks) or the "evil" option of killing her. You can also steal the potion (which is a mechanic not really explained in the tutorial), knock her out (which is often buggy or not working), or brew your own potion, which requires careful investigation of the room especially beforehand as the cauldron does not light up, so you might totally miss it.
What is missing is a more definite hint and way out of the fight with a prospect of other results. Why does not one companion step in and say exactly that? Or when entering the room, why doesn't Gale remark that there is an awfully big cauldron in the corner ready to make anything? Why does Nettie conveniently ingnore your companions running around with tadpoles?
Another situation is the tadpole crawling out of the dead dude at the bridge. You need to pass two pretty hard checks to stomp it and failure will result in disapproval from companions. That is enough of an incentive to reload multiple times. Your Illithid situation is also a prime example. I never saw the Illithid the first time, the camera was awkward, it did not light up, and the people actually did not dig at his body, but 2m away. In the cinematic dialogue it was not seen either, I just figured it was a meter or so below ground. After the fight you are again in a two check situation to gain control back, if I recall correctly. I think you could also totally walk away from it, without interaction. As said, I did not see it at all, as my focus was on the spot they were digging at, the illithid did not move, did not light up and it also blended into the environment.
There are several other encounters where the passing of a skillcheck will unlock more content, fluff, a reward or a shortcut. Fails will generally lock you out of this, you gain nothing and this is a mistake if you want players to be immersed and incentivized in failure as well. And as said, workarounds often do not help, because the checks are made difficult through having multiple to gain the same result and that can check for different things. Entering conversation with a certain companion also requires intensive knowledge of the conversation, which in turn requires a reload.
So you fight against the odds, you fight against psychological and haptic failure and you fight against the UI and glitches/bugs. They might give opportunities to think outside of the box, but they do not hint at it enough. At the very least they need a hotkey that makes interactable items light up, or a toggle. While at it, they should also do the same for surfaces, light level and beneficial geography. Add audio cues and companion remarks for situations. It would also help to have the option in conversations to let your "professional" take over.