The app devs, including Selig, often, said they were perfectly fine and found it quite reasonable that Reddit wanted to charge for API access-- they even looked forward to it because the y believed it would. open up access to previously walled-off parts of the API such as chat, polls, and other features only available in the native app and the website. This was public info, and users also looked forward to this.
The problem came with both he outrageous pricing and the absurd 30-day timeframe. Then, further with spez's refusal to be flexible by listening to the reasonable complaints of the devs, slanderous accusations against Selig, profound and entitled disrespect towards the mods, and shitshow parade which started with his mind-boggling AMA and then continuing by taking interviews with any news agency that would talk to him, further spreading the lies, slander, disrespect, and disinformation-- ending by praising the king turd of tech: Elon Musk.
THAT is what provoked the outrage, protests, and overall "uprising". THAT is what is killing Reddit.