You can't compare item RNG to cardgames like Magic or Hearthstone...
At least in card games both players start out with the same number of cards in their hand and have equal access to their other cards.
Sometimes you just straight up get SIGNIFICANTLY less items in TFT, and not always because you did anything wrong. The issue is that. save for the shared draft rounds, it's completely random whether you get items at all. Even if you beat the neutral mob phases there's still a decent chance you get nothing. Even dragon has a chance to give nothing and he's significantly harder to kill than other mobs.