I've made many native apps (including our own native Android app) and performance issues are definitely still a thing with native code :P
The amount of work was non-trivial, however, in absolute time it was a few weeks of work that we have only done once after first creating the app many years ago.
It's likely that we we would have considered doing something like this even if the app was in pure iOS - Discord has gotten much bigger.
Mobile teams I have seen for apps at scales similar to Discord tend to run anywhere from 10-20+ dedicated engineers. By comparison I believe we have been able to accomplish a lot with a much smaller team.
The amount of work was non-trivial, however, in absolute time it was a few weeks of work that we have only done once after first creating the app many years ago.
It's likely that we we would have considered doing something like this even if the app was in pure iOS - Discord has gotten much bigger.
Mobile teams I have seen for apps at scales similar to Discord tend to run anywhere from 10-20+ dedicated engineers. By comparison I believe we have been able to accomplish a lot with a much smaller team.