As managers, we easily get frustrated with developers. Maybe they can’t build a certain feature; or a bug fix you deemed critical to your business is too far down the backlog for comfort.
I agree with your opinion.
I think it will be hard and very stressful for your team if you don’t have deep knowledge about what exactly going on. And how things going from backlog to done.
I’m always trying to defend developers - because they are doing a very important part of the job, you know. And if something is going wrong - this is where the manager should stand and make things rolling. This is how I tried to do in my prev company.
In my opinion, if you hire a manager into an existing dev team - you should understand that it will take around 6 months before the manager will be able to set up clear communication with all parts of the process.