I use it for everything, because I connected my external monitors through the eGPU. https://wiki.archlinux.org/title/PRIME has a few methods for running only selected applications via the eGPU, but I haven’t tried them. Edit: See also https://wiki.archlinux.org/title/External_GPU#Xorg for eGPU specific setups.
It’sintended to be used when the cookies are actually required for the app to work. For example, to preserve your login, you need a cookie, no way around. Unfortunately, as mentioned by others, it’s often abused