Silly question: Does this broadcast button create some sort of event that ends up effectively spamming everyone's feed? My assumption is that it's a tool to spread notes to newly added relays which may not have access to the notes yet: https://image.nostr.build/af73cc4c8f1309b62fbd7a33e6529973656ecb33939bcaf69c479c9f8fd555a3.jpg
It won't create an event. It will push the event in question to your relays, and it will be ignored if it is a duplicate. It's unlikely to spam anyones feed, unless it's an event that would have appeared anyway (if it had existed).