https://www.youtube.com/watch?v=q3ar91rGQS0
If YouTube is taking away your subscribers, chances are you had a few inactive accounts subscribed to your channel. YouTube deletes inactive accounts regularly, which often leads to a decrease in subscriber count for many content creators. Site-wide subscriber purges used to happen in the past, but this isn't as common now.
Gaining subscribers can be a difficult process. So, when you see subscribers getting taken away, it can be quite disheartening. It's important to remember that the subscribers being taken away are all inactive accounts. Meaning, none of these subscribers were active viewers of your videos, making them essentially worthless.
Does YouTube remove inactive subscribers? Yes, they do. However, you must know the right definition of "inactive" in this scenario. Inactive, in this scenario, means accounts that are either fake or have been unused for a long time. Subscribers that haven't watched your videos for a while aren't inactive- only accounts themselves can be inactive.
For example, if someone subscribes to your channel but doesn't watch your videos, they are typically defined as being an inactive subscriber. When it comes to YouTube, however, this subscriber won't be considered inactive if they still watch videos from other channels. An inactive subscriber on your channel might not be on another channel.
Most inactive subscribers that are removed from YouTube channels often end up being fake accounts. Many channels use fake accounts to inflate their subscriber count, making it seem like their channel is more successful than it is. YouTube removes these fake accounts quite frequently, as manipulating subscriber count is against the YouTube Terms of Service.
If a lot of inactive subscribers are removed from your channel, your subscriber count will drop. However, this isn't a bad thing, as these subscribers will not have been providing you with many benefits. Many people strive to have a large subscriber count, but at the end of the day, subscriber count itself doesn't play a role in achieving success on YouTube.
Blessings