Sorry to disagree but there is a deduction for crumbling foundations. If you look on page 4 of the Publication 547 you have linked you will find this:
Special Procedure for
Damage From Deteriorating
Concrete Foundation
Under a special safe harbor procedure, you can
deduct the amounts you paid to repair damage
to your home caused by a deteriorating concrete foundation containing the mineral pyrrhotite. Under this procedure, you treat the
amounts paid as a casualty loss in the year of
payment for amounts paid prior to 2018. See
the note below for amounts paid after 2017.
