You turned

anyone with 20 seconds of (network) access to your PC can extract your 12 word backup phrase

into

anyone with 20 second access to you PCs network

I really don't want to argue with you but adding ("network") time was an irrelevant detail related to time and not method of access. We're talking access to local storage there, whether it's accessed remotely or not doesn't change the time in any significant matter.

You completely changed the meaning of the sentence by miss quoting.