CPUs and GPUs are designed so they can run reliably at up to 100C. I agree that high temperatures can shorten the life of electronics but if it shortens the life from 100 years to only 50 years or 25 years, does anyone care about that? Probably not. My closets are full of CPUs, GPUS and other electronic gadgets that have all been overclocked and that all work perfectly fine still. Most people buy something new long before something craps out due to heat exhaustion so I don't think you need to worry about your GPU idling at 60C.

As long as you do regular maintenance and keep your heatsink and fans clean, your laptop should last a long and healthy life.

No matter how you have ThrottleStop setup, it can not prevent your CPU from throttling if it reaches the thermal throttling temperature that Intel set at the factory. Intel's CPUs are very well protected at the hardware level no matter what software you run. Thermal throttling typically happens at a core temperature of between 98C and 105C for the majority of Intel Core 2 and Core i mobile CPUs. Intel obviously has a lot of faith in their CPUs being able to run reliably at these temperatures.

At work I used to use a Dell Latitude E6410. As soon as I plugged that laptop into the docking station where it is connected to multiple monitors, it automatically disables the Nvidia GPU 2D speeds and forces the GPU to run at 3D speeds with 3D voltage even when you are doing nothing more demanding than surfing the internet or staring at the desktop. All this does is it creates a pile of extra heat within the laptop and there's no reason for it. Your Asus laptop might have a similar "feature". You can try monitoring your GPU with the GPU-Z program to see if something like that is happening to your laptop when it is idle.

As long as your laptop is running reliably at its rated speed, this is mostly just an annoyance due to poor design.