All the numbers thrown around about the lend lease program are military accounting and do not impose almost any actual costs to the US tax payer, basically just the cost of shipping which is minuscule compared to the Military budget let alone Entitlements. Therefore, the comparison of essentially military funny-money and actual Entitlement increases is just hyper-partisan nonsense.
We don't have $6.2B worth as it's military accounting value, not actual value. There are no buyers for this obsolete equipment apart from Ukraine, and no longer any use for the US military. The money put into the equipment is a sunken cost and the US Gov has to incur the ongoing cost of storage or decommissioning. This entire controversy is based on a seemingly willful misunderstanding of why the military gives obsolete equipment a monetary label and then an equivocation of that monetary value label with actual money.