Sounds like the role may be mislabelled if this is what he's doing routinely. I think the key question for me is whether he has responsibilities that are expected of him that he is unable to perform because he is doing this work instead.
Also, does your company have a separate formal architect role? Is it hard gated approval (this doesn't move without my stamp) or is he just keeping an eye on things?
Also, does your company have a separate formal architect role? Is it hard gated approval (this doesn't move without my stamp) or is he just keeping an eye on things?