This result- where the government backed down, was not expected by anyone. Ever since the Beijing-picked government stared down the Umbrella Protests in 2014, it's been a death by a thousand cuts to Hong Kong's autonomy.
After talking to a friend who works for one of the pro-Beijing parties, it turns out the biggest fear for the Chinese authorities wasn't related to HK at all, but Taiwan. China has spent so much resources to promote friendly candidates for office in Taiwan and this HK debacle has instead emboldened the incumbent president of Taiwan, who is not at all friendly towards Beijing. In fact, she won her party primary and is now well positioned for the elections next year. As it turns out, as important as HK is, Taiwan is more important to Beijing and anything that provides fodder for Taiwan's independence leaning party is not allowed.