These blocks tend to be reactive, so if a blocked app starts using Tor, Iran will block Tor fairly quickly. So in return for a short-lived regain of the use of

These blocks tend to be reactive, so if a blocked app starts using Tor, Iran will block Tor fairly quickly. So in return for a short-lived regain of the use of Signal, all of Tor gets blocked. This proxy arrangement is better because folks who start them tell their friends in Iran, who tell their friends, but it isn't listed publicly, like most Tor entry nodes are. When the authorities find a proxy and block it, they only disconnect a subset of Signal users, who hopefully have other proxies they've learned from other friends or friends-of-friends. So now the blocking is trying to put out a thousand small fires that they have to find one-by-one. <I have consulted for the Signal Foundation in the past, but not recently and haven't talked with anyone there about this>