There is another Q that deals with something similar: Every "close" has its thorn: replace "close" with "on hold" for the first five days
They confirm the anecdotal and peer-agreed notion that "closed" sounds final:
The word "closed" sounds final. Now, we don't mean it to - but right
out of the gate, we're ...
We've actually already tried doing something like this via an "on hold" state. While that change was active, closed questions would instead show as "on hold" for the first five days to encourage users to edit questions and be more friendly to new users.
However, further research showed that none of that actually happened and that the &...
A post is usually closed for a reason: It might be off-topic, unclear, a duplicate, etc. Closing a post just because you do not want any more answers is not the way to go; if you've found an answer that solves your problem, and you don't need another, you can just answer your own question, and accept it to show people that you have solved it.
Electrical Engineering does have a close vote button. You just don't have enough reputation there to have close-voting privileges yet though, so you don't see the button. You need 3000 points before it becomes visible.
You can still flag the question and put it in the close vote queue that way.
What is the reasoning for making bountied questions immune to close votes?
Well, the point of a bounty is to attract new answers, and those can't be posted on closed questions.
If you see a bountied question which needs to be closed, flag it for ♦ moderator attention, explaining that you can't use a regular close vote since it's bountied. If they agree with ...