Kessler syndrome - hundreds of thousands of tiny shards would explode at the point of impact ripping into other satellites and rendering them defunct (causing more collisions). An exponential growth would occur which would result in Earth orbit being unusable. This might effectively lock use of Earth orbit away for centuries.
See the video by Kurzgesagt - “End of Space: Creating a Prison for Humanity.” [1]
See the video by Kurzgesagt - “End of Space: Creating a Prison for Humanity.” [1]
[1]: https://youtube.com/watch?v=yS1ibDImAYU