From my perspective it is to stop loads of stupid code/stupid solutions even way before it is written down as a task on your favorite task tracking tool.
You seem to be arguing into promoting seniors into architects. The GP is arguing into promoting them to management.
If the one hard problem your place has is organizing all the easy problems so they add to each other, turning your seniors into architects makes a lot of sense. And that's a very common situation.
But the GP's motivation for moving them into management is basically that the organization is dysfunctional. That's not a good reason, although it may be the only thing you can do.
I am mostly thinking about technical team lead role which is not an architect and not managerial role.
Team lead does not have time to code most of the time but does code reviews and attends meetings with architects and others and works on aligning stars so things happen. Then also has to stop stupid ideas or propose how to better solve a problem for a customer.
But as I read GP post again it seems he might mean actual management.
A tech lead codes less, but they directly contribute to producing the engineering artifact.
They are an "actual contributor with direct responsibility."
However, all meetings that the tech lead has with people OUTSIDE the team, is communication overhead to be minimized. So a tech lead combines code review, external communication, and direct work on the engineering artifact.
Communication overhead is the problem. Architects, people managers, are all overhead roles. They don't "actually contribute" to the product.
The more strictly define it, it's not actually about the "fulltime role." Maybe the senior engineer doesn't change their job title, but their schedule becomes less about coding, more about communicating.
It's about minimizing the amount of external communication that needs to take place per code deployment.
But not only to get any code to prod.
From my perspective it is to stop loads of stupid code/stupid solutions even way before it is written down as a task on your favorite task tracking tool.
That is what meetings are for as well.