I signed up for https://tweepsmap.com a couple of weeks ago, to have a look at where folk I was connected to were from. Got an email which included this info:
You are following a total of 2641 accounts
550 of them are not following you back
174 have been inactive in the last 2 months
432 have been inactive in the last 6 months
I though I'd have a look at them. I've an old copy of Martin Hawksey's Export-Twitter Followers google sheet from 2011! I gave this a whirl this gave me a couple of sheets, one with followers and one with folk I follow. A quick google got a formula to extract a list of the 550 folk who I follow but don't follow me. I thought I would have a look and unfollow the ones who were not an extra good source of info.
I pasted bits of the links into TextMate and did the multi-line edit thing to put "open http://twitter.com/ " before each user name. Running this from the shell script bundle opened a bunch of tabs in Safari which I could quickly go through. I found 50 tabs at a time were ok, 100 slowed Safari down too much.
Quite interesting to see who was not following me, most were folk who must have deleted me, my following is usually in response to someone following me, a quick look at folk who do and if they are not a business, interested in the same sort of thing as me I follow back. I guess they may get fed up with my propensity to post nonsense.
An hour later and I am following 2234 folk. This is still way to much for my attention span, but it is a start.
Interesting too to feel small spikes of hurt when I see some folk have stopped following me.
I also found I follow quite a few bots, including one I created several years ago and had forgotten about! Of course I kept following these and several big name (education world at least) ones that are good value to me.
Generally though I want to be connected to people who will potentially listen & talk to me.