Saguaro

Repasting finally solved the issue, I used Thermal Grizzly Kryonaut and the temps are now under control at about 75-80 on the CPU and 75 max at GPU.

my old laptop (bought in 2011) ran the cpu at 70c idle, after 5 years (when i was computer literate), i cracked it open and apparently the insulation layer around the die (mine was orange, but yours is black) was covering part of the die, making it having a bad contact
 
makes me kinda avoid asus laptops in general

If your ROG laptop runs hot and thermal throttles, it's quite possible that it is because the stock thermal paste.
 
I have got a Strix Scar III G531GU and had CPU temps over 95C of course with thermal throttling, so I have decided to void my warranty and repaste the machine.
The chosen paste was Thermal Grizzly Kryonaut. 
 
After repasting, i got temps around 20C lower, so on a combined stress test with the CPU and GPU pinned to 100% it was around 75C on both.
 
Just a heads up so that you know what are you dealing with and how much performance can be left on the table. In some games now I have 20-30fps more while the laptop is quieter.
 
I have attached 2 images of the stock thermal paste (wich was more like thermal concrete) application and hardness.
 
 

There are not.
FOrtunately, I managed to solve the issue.
Here's how: https://superuser.com/questions/1097780/prevent-screen-turning-off-when-lid-is-closed  (Using the gpedit.msc method) 
Now everything works fine.
 
Thanks for the help @Enderman!