> the fact it’s likely already cached on the browser from a common CDN makes it seem quite silly to go out of your way to remove it.
This is a missconception. The problem of multiple CDN's and various patch releases of shared libaries means the hit rate is only likely to be in the 2% region.
https://www.root777.com/appdev/does-using-google-libraries-a...
Developers tend to focus on their use-case too much.
People hate farrrrrr too much on jQuery. Sure, you should remove it when you can but the library size plus the fact it’s likely already cached on the browser from a common CDN makes it seem quite silly to go out of your way to remove it.