Getting rid of that alt section and moving any Ann threads that are posted there into the trash will bring about even more readability.

Why no one wants to trash ICO announcement topics?
Isn't it because it is allowed to translate topics in local sections, no matter no one reads them?

There's little to no demand for alt coins there [...] It's not needed.

And tons of hours to clean it from useless spammy topics/posts...

That is not true.