This may help you out to get started, then read the previous article I linked.

https://medium.com/@nopara73/explain-uasf-like-im-five-ae879...

It is not a simple topic with two sides. It has very technical details as well as economic incentives for both sides which leads to a lot of game theory.

The Chinese? miners won't upgrade the protocol b/c they are making money, and Bitcoin is running into some scaling issues with the 1 megabyte limit, so the users are revolting with a 'user-activated soft fork'. Something along those lines.