Hard to say. Why would you load a new config if a valid config is already loaded?

Maybe the new config has a new update. Who knows? Do we want to keep operating on the old config? Maybe maybe not.

But operating on old config when you don't want to is definitely worse.

Of course it depends on the situation. But I don't see how you could think that in this case, crashing is better than stale config.

Crashing on a config update is usually only done if it could cause data corruption if the configs aren't in sync. That's obviously not the case here since the updates (although distributed in real time) are not coupled between hosts. Such systems usually are replicated state machines where config is totally ordered relative to other commands. Example: database schema and write operations (even here the way many databases are operated they don't strongly couple the two).

Because stale config could easily go unnoticed for a long time.

Crashing is generally better than behaving incorrectly due to stale configs. Because the problem would get fixed faster.