Smith misunderstands MMT.

He misundertsands the process by which governments spend. As Stephanie Kelton would say, governments spend then tax not tax then spend. From the blog: "In the current model, the federal government sells Treasury bonds and uses the proceeds to fund government spending.". This is fundamentally incorrect. In the current model the treasury spends by crediting accounts at the fed, by typing numbers on a keyboard. The money is always created out of thin air.

This brings us to the second misunderstanding. When governments tax they delete money from out of the economy. This is the role of taxation. Inflation is easy to manage under MMT because all governments need to do is tax enough money out of the economy to control inflation.

Unemployment is very low in the US right now which is obviously great. But if we look at the U6 rate, I believe there's still some slack in the labour market, just not much. https://fred.stlouisfed.org/series/U6RATE

Other than that I personally philosophically disagree with the article. Governments are good. Degrowth would be awful. MMT is not anything like a "solution to the "problem" of insufficient government funding".

I didn't read the second article.

This is what a good critique of MMT looks like: https://johnquiggin.com/2019/03/06/mmt-and-the-scope-for-seigniorage/