I'm not saying "because (only)dragons". I'm saying because:
- A character can reliably survive extreme falls repeatedly, no chance of death whatsoever. No broken bones. Nothing.
- A walk in lava causes no permanent damage.
- Giants, oozes, all the weird and impossible monsters.
- Some creatures are inherently and non-magically immune to some spells by means of legendary resistance.
- All the magic.
- All the weird playable races with barely no regard for movement speed vs size.
The person I was replying to was asserting that the setting attempts to be realistic. It isn't.