Let me word it differently.
You classify tickets into categories A,B,X,Y. You always clear out A and B before doing anything else. As a strategy to have "zero unresolved important issues", it's valid.
The disconnect is between the "Bug" ticket category, and the actual definition of what a bug is.
"Web font is being downloaded when it should be embedded in the app" is clearly a bug, by the normal definition of bug.
This system classifies by priority to get Critical/"Bug"/Other, and it further divides the lowest priority into new features vs. changing features. At no point does it ask if something is a mistake. It doesn't care. So it shouldn't use the word 'bug'. It tricks people into thinking it's something it's not.