Probably only China Mobile and education network users can open it extremely fast; China Telecom and Unicom are painfully slow. Although latency is very low (under 100 ms), QoS caused by human and objective factors results in a high packet loss rate that should not be underestimated, affecting download bandwidth (and image loading times).
In an ideal situation, on the first load, all static files such as js, css, and even previously accessed post data should be cached locally, but the current Discourse does not implement this. Therefore, when a user’s network to the server, which is currently in Hong Kong, is poor, clicking refresh requires waiting, and returning from a topic to the homepage also requires waiting, which is indeed very frustrating.