If you played any older DnD editions youd probably run into very much the same stuff. "Im gonna flood the dungeon" "Im going to set everything on fire" "I use a ten foot pole to inspect EVERY SINGLE FLOOR TILE IN THE DUNGEON"
I cannot understand how this is "not DnD" to you. What is DnD? Just playing the rules with no roleplay and no trying to gain an upper hand? DnD doesnt play like that. it never did. Hell i remember two years ago everyone as PSYCHED about Goblin Slayer and how cool it was that the characters in that series improvised like an actual DnD party instead of just running up tot he monsters and beating them up. And now its suddenly bad because larian is doing it?
And im not even going into the absolute cheese you could do in the infinity engine with absoluteley rule breaking stuff like kiting