The answer is simple: this card game was originally created for children
309.6: If a players venture marker is on the bottommost room of a dungeon card, and that dungeon card isnt the source of a room ability that has triggered but not yet left the stack, the dungeon cards owner removes it from the game
If you are unable to cast a card from exile after it is placed there via Rebound, the card remains exiled for the rest of the game
Sharp, square corners are essential for high grades
Again, more new-to-Magic cards means more opportunities for high-value goodies that arent being counted here, so dont shrug the deck off completely
If you want to get better at Vintage Cube drafting, I recommend checking LSVs Youtube channel where he posts daily draft videos