Adding subtitles without having to turn on "replace" in sounds.json

Normally, you can not add subtitles to sound events that lack them (example: music sound events) without setting "replace" to true. This, in my opinion, is a problem, especially when it comes to adding subtitle popups for music, as not only are you forced to paste all of the music tracks to the sound events, but also, with every new version that adds new tracks to the game, you need to manually add them to their proper sound events.

I see such a change as more intuitive, as you're not replacing anything, you're simply adding more. I believe that allowing resource packs to add subtitles to sound events without such more easily would be a small, yet very welcome to some change, that, as far as I can think, would not negatively impact any aspect of the game or its resource pack creation process.