The screen froze. It happens.
It may cause damage to the pc if you shut it down without a backup, but that’s an fyi you likely already know.
As for the damage it is doing to your system, it shouldn’t be damaging it directly.
Have you checked the system requirements and if your drivers are up-to-date? I assume you have and it isn’t the only thing which may cause a screen freeze like the one you had.
If possible, could you explain what you were trying to do before it happened?
You may find that after a fresh install the game may be playable again (since you already removed it anyways). It is worth trying, but you don’t have to. It could help to resolve similair issues in the future if you do though.
See also: How to be a pro PC bug hunter (PLEASE READ).