While I do think the HP bloat for low CR enemies is a real issue and that the Gith encounter is pretty brutally balanced, it's worth noting that enemies in 5e aren't built like players and don't have class levels. They generally will have more hit dice than their CR and usually more than a PC of a specific level does (e.g. a Hobgoblin Captain in the Monster Manual has 6 hit dice despite being a CR 3 creature).
Nere's stats aren't really that ridiculous, atleast when it comes to HP. 72 HP is pretty normal for a CR4 boss enemy (an Orc warchief is also CR4 and has 93 HP).
The druid's transforming into weaker bears actually makes sense according to the rules if we assume they're circle of the land druids. A 4th level circle of the land druid is restricted to at most a CR 1/2 creature, which means the best bear they can wildshape into is a black bear (19 hp). 4th level Moon Druids can wildshape into CR 1 creatures such as Brown Bears (34 hp). The polar bear transformation that players can use is just a slightly weaker version of the brown bear statblock (slightly less hp and d4s instead of d6s as damage dice).
And that's what I was trying to say. Thank you.
And I totally think crafting every NPC in BG3 using PC character creation would be a nightmare. Dear God. As it is, it seems like they kinda did do that, but think about how many enemies there are. 30 in the goblin camp alone.
