The revenue for these businesses cratered. It cratered due to government actions. For service businesses or businesses that sell to service businesses the revenue is zero or nearly zero. The reason why the businesses needed X employees before is because to support Y revenue pre-closure X-1 employees were not enough. In order for the the payroll portion of a loan to become a grant a business cannot decrease the number of workers even though it has no revenue to support them. Reductions in payroll costs reduce the forgiven part of the loan. Reduction in a headcount reduces the forgiven part of the loan.

Essentially, in order for a loan to be treated as a business makes the following bet:

"In no more than 2.5 months from the moment the loan is funded the revenue will return to pre-closure levels"

The non-grant part of the loan (or entire loan if it no longer qualifies) must be repaid in 2 years at 1% APR.[0]

The only real play for a small business that is planning on being around for a long time is to get the loan based on the top payroll number, immediately lay everyone off taking 1% APR hit and repay outstanding loans with higher APR. This is only applicable to businesses that have a lot of cash in a bank.

[0] Before Wells Frago/BOA/Chase etc complained to Treasury that they were not going to make enough money to "make it worth for them to do these loans" the repayment terms were 0.5% APR for 10 years.