As I said, just because you didn’t understand what the field is for doesn’t mean it’s a bug. Poor documentation is not a bug, it’s just, well, poor documentation lol.
I don’t speak for Twitch, but it is understandable that it would be a mismanagement of resources to develop a feature for a deprecated API. It’s more efficient for the devs to focus on Helix, especially when what you’re asking for isn’t going to be largely used (many devs have already migrated to Helix, and those that haven’t are unlikely to spend development time on a deprecated endpoint). Everyone else has their own workarounds and solutions that are appropriate for their individual use cases that will be sufficient until the endpoint for Helix is released.
Until then, you just need to be patient, you’ve made your point known, I’ve linked how you can submit feature requests so there’s always that too 