some of us like answering the same questions over and over again because a majority of people are dumb and forget
and in case you didn't notice, the simple questions thread is over 300 pages long.
and there's a search function that people neglect to use.
there is no need for this.
I think all your points illustrate a need for such a sub.
1) The people that like answering same questions over and over can answer them in the new sub. The majority of people that are dumb and forget could browse that sub as well. And there won't be any more "not this thread again" kind of response that could be seen as unwelcoming and is definitely unnecessary.
2) there're some questions that don't fit into the simple questions thread since they're not so simple and potentially more opinionated.
3) the new sub would be a direct answer to the lack of search function usage. having it exist is pretty much giving into the fact that some people don't use the search function. plus, there have been a lot of times the native search bar let me down and I felt more comfortable searching on Google and adding "geekhack" to the end of my query to get what I wanted.
The redundancy/clutter would be neatly packed in one sub rather than scattered everywhere. and people won't feel intimidated asking some questions. I'm assuming the target audience for this sub would be the relatively newer members that aren't that comfortable with the forum yet. Maybe expand the scope of the 'new members' sub to also allow for these types of questions by explicitly changing the title or something.