> However, the benefit is that we would then have plans (diagrams, specs, etc) to build it and one built we can iterate.

To me the current state looks like as if we

    1) recreated F-1
    2) had plans and diagrams
    3) iterated - first to the level of NK-33, then to the
       level of RD-270, then to the level of Raptors
    4) carefully put those original plans back on the shelf
       and forgot about them.

Yes we can't do F-1 today verbatim. We also can't do many other things, not easily - steam engines, telegraphs, airplanes, cassette players of the time would all require some re-engineering. We however can often do better using very different approach.

> However, the benefit is that we would then have plans (diagrams, specs, etc) to build it and one built we can iterate.

Hypothetically we've lost the diagrams,designs,knowledge to build a 386.

Is it worth building one today just so we can remember how, and then iterate on it?

No, absolutely not. The F-1 (and the 386) are ancient. Don't start from ancient and work up. Aim higher.

Sure you always learn something when you do anything.

> Literally can’t build an F-1 engine.

We can. There has been lots of work done on that already. But you wouldn't want to do an engine like it was done back then anyway. It would be crazy to do it the same way. A modern version would be better, better controls, lighter and so on.

> However, the benefit is that we would then have plans (diagrams, specs, etc) to build it and one built we can iterate.

Those would be more like constraints. So many things that are not the same anymore. You would literally reconstruct the economy from the 1960s first. That would be totally insane thing to do.

Its not because of 'lost knowlage' its because first of all, it just doesn't make any sense to do it the same way even if you could. Both the tools and the people are totally different, the structure of the economy is different.

I agree - there would be tremendous value in taking the 1960s approach, keeping it simple, and optimizing with modern electronics.

What they seem to be doing is a code rewrite while adding features.