Meh. They’re dealing with two orthogonal problems here:

1. There’s a right amount of documentation. It’s not zero, but it’s also not “every thought you’ve ever had”. The more your documentation can be generated or validated automatically, the more you can reasonably sustain.
2. It’s expensive to be wrong. You can deal with that by either doing pre-work in order to reduce the chance you’ll be wrong (which increases the cost of later finding out you were wrong), or sprinting towards a deliverable in order to minimize the cost of being wrong (which increases the chance that deliverable will be wrong).

You’re probably better off looking at each of those problems independently first and deciding where on the spectrum your team would thrive. RFCs might hit the sweet spot for both. But if you don’t ask the deeper question, you might just make things worse.