As I can see for myself and on the numbers under the streams I watch I noticed that often the number of follows is about 100x higher than the actual views and so I would recommend to remove inactive users in a process similar like follows:

1. After not watching a followed streamer for let's say 1 month the user gets a notification email that he is inactive for this specific channel and can be unfollowed if inactive for much longer.

2. After let's say 2 or 3 months of not watching a channel the user gets an email that states that if he/she does not watch this channel once in the next two weeks, he will automatically be unfollowed from this streamer.

3. After the threated amount of time passes without reaction the user will be unfollowed from the regaring streamers channel.

4. A settings option can be added that allows restoring single follows that have been undone manually or automatically. (For security reasons and if one does not have access to the internet for a long time)

This system should be balanced regarding the time limits etc. but I think that it could work just fine for giving streamers a better overview of the general amount of active people at all.
But the feature should be aware not to toggle if a streamer does not stream for a longer time so he/she does not automatically lose viewers because of being inactive.