“But it should be noted that Medicaid (pure welfare) and Medicare (funded by its truly eligible users) are VERY different things”
Medicare is not completely funded by its truly eligible users. Not even close. So from a taxpayers perspective, there isn’t much difference between a Medicaid user and a Medicare user - sorry to burst your bubble.
We are going to “single payer” because there is no way Medicare and Medicaid “cost shifting” to private insurers can occur with such high numbers of complete freeloaders (Medicaid), or mostly freeloaders (Medicare).
“We are going to “single payer” because” that is PRECISELY what the government intended to happen when Medicare was first forced upon us in 1966!
Single payer has been the plan since well before then, BTW.