Have a PS4 Pro that becomes noisy when playing graphically demanding games such as Gods of War?
When dust builds up on the heat sink and the fan, the fan has to run at a higher speed to keep the heat sink at the temperatures set in the PS4 tolerances.
The fan can only go so fast until its max RPM is reached, at that point thermal damage to the GPU and any heat sink paste can become damaged.
It is likely it will need a service, below is one done with before and after shots
Pictures Below are after a Full Service
Fan and Heat sink Thoroughly Cleaned
PS4 HDMI, USB, Ethernet, Camera and SPDif sockets cleaned