Can you distinguish between a message and a messenger? Of course they have further, dangerous plans. But the suggestion at first sounds good, which is to be expected. From the article:

The now-public roadmap includes proposals to strip power from the European Commission and the European Court of Justice. It also calls for renaming the EU to the “European Community of Nations.” Power, according to the document, should return to the individual nation states of Europe.

“These proposals essentially amount to the complete dismantling of the European Commission, which would be reduced to handling only trivial matters,” explains Szabolcs Panyi, the journalist who obtained the document.

Nieuwsuur also spoke with one of the Polish authors of the plan, Zbigniew Przybyłowski of the conservative Ordo Iuris Institute: “We are calling for the restoration of democracy, freedom, and the sovereignty of nations. You could call that a power shift.”

The arguments:

Why would a scaleback to national states not be democratic?

In short, exactly because - as you say yourself -it is a ‘scaleback’ and a ‘limited role.’

We need to go forward as a larger EU would also be stronger as single national states.

Those are two things, power and democracy.

You are willing to get more power while not caring about democracy. If the EU moves forward as is, there will be less democracy.

It could even be false flag. What if the Heritage Foundation wants that concentration of power?

Why do we need it? The EU started as a project for a free market. Even if we need a strong military we can do that without all the other concentration of power.