MiaRN1042 – if you're referring to the Theater Mode trick. There is no fix for the ambient light sensor being too sensitive, that is something Apple will need to fix. Mine does appear to dim "sometimes". The Theater mode is what I use at night after I've gone to bed (set with an automation). When Theater mode is on, I can rotate the crown (provided I've allowed the rotate to wake option), and the screen SLOWLY increases from the 1nit to however bright I want it (up to the max set in system settings). I do this if I wake up and need to see the time, I just nudge up the brightness.
Otherwise, I've now set my System Settings to "Medium" instead of low, and I've had better experience.
-*- however, if your device is failing to go to the brightest setting, and is dim in natural light, then there may be a physical issue with the sensor that needs to be replaced under warranty. It is hard to test the dim setting in an Apple Store I agree.
Good luck, I'm waiting for the next software update to fix a GREEN flash that happens on the screen as I take my watch off. It is subtle, only for 1 frame flicker, but it is annoying.