You're more right than you know. It's already in their bill.
Here it is:
The bill raises enough revenue to pay SS benefits and collect the general revenue. But you knew that.
The rubber meets the road where pols have to vote or not to raise or decrease the rate. The rate which is applied evenly to ALL individuals regardless of income level.
Illegals will have to pay it (only legal residents with SSNs get the rebate). Tourists will have to pay it. Imported goods will have to pay it. OTOH our exporst will leave our shores withOUT tax costs - making them 25% cheaper overseas.
The portion you posted only guarantees that the SS benefits of retirees will be paid.