1. It is available way too often
...there is no obstacle or risk to long resting in BG3. [...] At first, I tried playing as I would in a campaign or any other game, and I long rested only when I had fully run out of spells and potions. This playstyle seemed to also be encouraged by the game telling you about the tadpole taking over you and time being of the essence. I quickly found out that not only is long resting extremely important to advancing the main story, not doing it enough can also make you miss out on a ton of content. I started to long rest more often and found everything became very easy. I could long rest after any out of combat spell cast, ensuring my characters always had full spells without missing a beat.
Exactly this for me. I don't enjoy missing content [that there is no good reason to miss - companion cutscenes should at least be queued up instead of skipped], but I also don't enjoy long resting after every fight or two as it makes the game trivial. I also think the premise of "you have a tadpole in your brain that could transform you into a mindflayer soon" is interesting, and it's disappointing that BG3 removes that urgency.