How meaningful are SPECTRE mitigations on single user desktops and workstations if the installed software is trusted?

What prompts this question is why some Spectre mitigations are considered meaningful on single user workstations or desktops.
When a piece of software is trusted by the admin or a user to run on a single user system, what is the purpose of… Continue reading How meaningful are SPECTRE mitigations on single user desktops and workstations if the installed software is trusted?