The bug
With the addition of data packs the /reload command likely reloads those now. However, the command feedback is still "Successfully reloaded loot tables, advancements and functions".
To remove the need of updating this text every time new content types are added to data packs, it would be better if the feedback was just "Successfully reloaded data packs".
Now in 17w45a it just says "Reloading!" in chat