Unsure which side you're on with this, but as a player that's indifferent to staff applications opening or closing, I kind of do get disappointed whenever I see an applications post in #announcements on discord - not because the app is closing, but because I expect a really cool announcement being made such as a new event or a major update.
On the other hand, I'm sure there are players out there that want to keep up with staff applications specifically, so having a separate channel or role would be helpful for them if they are interested in staffing.