Gracious! That looks as if a mouse crawled in there and died! I am somewhat astounded because any machine I've ever used would start to act up, either breaking thread or skipping stitches or something any time it got linty - a lot less linty that this. What kind of machine is that?!!!
I think one problem here is that a screwdriver is needed to get into that area. On the machines I am accustomed to, there is much easier access, and of course the more bother it is, the longer a person might put off doing the necessary cleaning. That's just human nature.