Well... true. Because everything is a product of our experiences and memories, there'll be some level of meaning in everything.

But, well, think of an earworm. If you have a song running through your head, it doesn't mean you like the song. It might even be that you hate the song, and that you are trying not to keep hearing it. All that it really means is that the song is stuck in your head, for whatever reason. If you probe more deeply, you might come up with a reason (the beat is unusually catchy for you, maybe), but it doesn't really matter. You could just dismiss it as noise.

Similarly, if an upsetting idea pops into a person's head, it might stick around just because it *is* upsetting. We remember things that make an impression on us. So, sometimes the meaning is just "this is upsetting for me to think about, and I can't keep from probing at it, just like my tongue will probe an achey tooth."

So there'd still be meaning ("this upsets me deeply"), but the lesson of the meaning might be "so I can blow this off (as best as I can) and wait for it to stop bugging me".