I recently deleted a large number of tags (~20k-25k) from one of the categories that publishes news items. These tags were contributed by our authors and added no value to the site. As a result, Google's bot is now noticing a LARGE number of 404 errors (~90k) on our site and as a results has pushed our rankings down. Though Google says that 404 errors don't affect, our observation is bit different.
After experiencing the downwards traffic for over a month now, I've decided to redirect all the 404 pages originating from the deleted tags to home-page permanently. I'm not sure whether this is a right step; but that seems to be the only option that I have.
For every 404 resulted on domain.com/tag/ , I want to setup 301 redirect to home page.
I'm a complete noob when it comes to redirects and can't take chances on messing up with these.