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Sure, but this could confuse new users (like me).
It isn't hard to implement a filter that removes every "#" symbol from the tags area.

the team probably has more pressing issues than this one. Just enter your tags without # is #easy

I agree, but I also see it from the new user side. It would be a 2 minute task to add a function the removes # from the tags area. If nothing else, then just if # is the first character.
I don't think it's a very pressing matter, but it would definitely be a great improvement
!BBH