"It's my understanding that the rules associated with forgiven debt still apply."

So far they don't for PPP loans. The loan forgiveness is not taxable.

But the expenses paid with the PPP loan money are not deductible (as of today 10/19/20).

I have no idea what, if anything, will be added to tax forms. I don't think many people will get PPP forgiveness in 2020. I think it will be a 2021 event.