Deepslate can be destroyed by ghasts

Deepslate can get destroyed by ghasts, which is very annoying. Cobblestone is immune, but deepslate should also be immune since it has more than 4.034 blast resistance.

 

How to reproduce:
Make a platform out of deepslate
Stand on it
Spawn a ghast
Go into survival mode
See what happens when the fireball hits the platform

What I expected:
The explosions will do no damage

What I saw:
The ghast fireballs started destroying the deepslate platform