Conveyor belt is wrong. The term you're looking for is transmission channels. MB is turned into M1 through lending. M3 is turned into M1 through collateralisation and demand stimulation, among other effects.
> If you have a dollar in a checking account, it's in M1, M2, M3 and M4 at the same time.
Yes.
> A purchase commitment or a capacity guarantee on Nvidia's balance sheet is just a contract. It isn't in any aggregate
Of course it is. Why do you think the SPVs want the commitment? They turn around and issue commercial paper and get bank loans and get bonds underwritten against those commitments. All of which turns into checking account deposits. Those SPVs also get a credit rating which lets them sign construction contracts which builders turn around and turn into deposits.
> Banks create deposits when they lend and they're constrained by capital and loan demand, not a reserve ratio
Banks are constrained by capital and liquidity requirements, on one hand, and loan demand, on the other hand.
> if money is being created here, it's the lenders who are creating it, not Nvidia. In this case, Nvidia isn't a bank, it's a credit enhancer
Yes. When the Fed buys Treasuries and increases a bank's reserves at the Fed, it's not actually doing anything in the real economy. The banks then have to turn around and increase lending. If, as you noted, loan demand is stagnant, they have to cut prices, i.e. rates.
The Economist is comparing Nvidia "enhancing" credit conditions in a manner analogous to the way the Fed does. By creating a base that stimulates lending.
> that's not money creation and trying to pretend that it is only distracts from the real issues
It's absolutely money creation in the way a central banker or anyone in the money markets would talk about it.