Ender crystals and beds don't blow up players if they are lower by 1 block

How to reproduce this bug:

1. Summon end crystal and go down 1 block lower than it is.
2. Blow up crystal
3. Waiting: The player dies from the explosion or takes a lot of damage if their armor was enchanted for blast protection
4. In fact: The player can survive even if they are unarmored