I believe (i haven't checked BG3 follows this)
But as you level up you do indeed gain a proficiency score improvement. Up to +6, so along with a +5 from a max ability score you can get a +11 to an ability score.

Of course Bards/Rogues get expertise so they can max out at a whopping +17 at max levels, which trivialises 90% of checks.

I did expect this ability score discrepancy but I mental forced myself to expect fails and have to deal with them. It's made the game more enjoyable for sure. But that doesn't mean I wouldn't prefer a Disco Elysium or perhaps a Fallout(certain score is guaranteed success) style instead.