The bolded section does not preclude somebody from serving two non-consecutive terms, it says that if somebody serves or acts as president for more than half of a term without being elected president (probably because they were vice president and filled a vacancy), they can only be elected to one full term.

Trump will serve or act as president during the next term, so the bolded section will not apply to him.

The bolded section does not preclude somebody from serving two non-consecutive terms, it says that if somebody serves or acts as president for more than half of a term without being elected president (probably because they were vice president and filled a vacancy), they can only be elected to one full term.

Trump lost the election and will not serve or act as president during the term beginning January 2021, so the bolded section will not apply to him.