That was an extremely well written explanation of his viewpoint on the future. Government providing guarantees leads to a weaker central bank and all the ramifications that would have.
Sure, a green loan guarantee spurs investment in that area but the business model must still be sound or it will be falter in the marketplace. And if government steps in and, say, also guarantees an energy price, that's just another form of taxation for the consumers that must pay the costs of a political choice in energy. This will quickly hit a wall of resistance from consumers if that particular technology is a mallinvestment.
Furthermore, the loan guarantees themselves might not be officially counted in the debt to GDP ratio, but rational investors will be aware of them and price government bonds accordingly. A state that over-guarantees bad loans will see trouble servicing their debt in the marketplace, and at least in Europe the well known structural fragility of the Eurozone will amplify those shocks and bring them into the foreground.
I don't know what the equivalent contemporaries would be, but in any case we would need to see public spending or nationalization on a scale incomprehensible to the current neo-liberal european business climate, not just some puny guarantees & price ceilings, which are not very sustainable anyway.
High inflation also only makes a dent in existing long duration debt. It doesn't do anything to reduce existing short-term debt, nor to reduce the real cost of new debt that comes from new deficits (at least for government debt).
(That is because short-term debt needs to be either paid off or rolled over.)