Twitter spam followers - is it getting a bit out of hand?

I'm not sure if I'm more troubled by spam followers than anyone else but it seems that I'm dealing with a handful of them every day (recently it was 15 in a one hour period once, but that's rare) and have lost count of them (it feels like it's comfortably over 100 of them). They all seem to have a similar format which makes me think that someone with better coding skills than me could probably rustle up some sort of script type thing to block them.

For a short while I protected my tweets (this means that anyone wishing to follow you must send a request which you can allow or block - and it's so much quicker to block spammers this way, fewer buttons to click) but I want my tweets to be public. Ideally my stream would be visible to everyone but people would additionally have to send a request to be able to follow (ie to receive your tweets in their timeline) and at the moment I don't think you can do that.

In the days of IRC (internet relay chat) it was easy to block people by using a line of text that recognised one or more aspects of their email address or username and would activate a 'deny' whenever they tried to join a channel. There's a good example on this page of how to do an IRC channel ban bearing in mind that people can change their username, or nickname and amend bits of their hostname.

Surely setting up something conceptually similarish to block anyone who - in these cases - has a username with X1758 (X and four numbers) and f*** in their bio (it's usually "I like to f***" or "I'm going to f***ing destroy you") is possible? They could then be flagged up as likely blocks for checking by whoever wants to do this. While most people probably don't use swearwords in their Twitter bio it's possible some do and this doesn't mean I don't want them to follow me but the combination of f*** and the X1234 style does seem to be a strong predictor for them being a spam account.

I have no idea what these spammers are hoping to do - perhaps I should follow one to find out... I am now following Carlita, let's see what happens.

Carlita is one of many Twitter users who shares the same bio and style of username. I don't think they post much either.

What I really don't understand is why Twitter hasn't set up something to catch these identikit spammers at source, they're not exactly helping my user experience.