Invalid elements aren't considered "serious errors" in terms of PCS - This is what the
official ISU rules (if you have a newer source with different information, please let me know) say about PCS caps:
"If a program contains
a Serious error, the maximum scores are listed below:
Skating Skills, Transitions, Composition: Maximum score 9.75.
Performance and Interpretation: Maximum score 9.50.
If a program contains
Serious errors, the maximum scores are listed below:
Skating Skills, Transitions, Composition: Maximum score 9.25.
Performance and Interpretation: Maximum score 8.75.
Serious errors are
falls,
interruptions during the program and technical mistakes that
impact the
integrity/continuity/fluidity of the composition and/or its
relation to the music.
Similar limitations must be applied to all levels of Skaters from extremely poor to outstanding."
Would you consider Yuzuru's popped 4S to fall into any of these categories?

(I personally wouldn't - he went straight into a transition and went on with his program as if nothing had happened.)