The patch made clear Blizzard was trying to prevent AV games starting empty on the Alliance-side due to premade groups dropping the queue and leaving the lobby without 30+ players at the beginning.
The latest patch had nothing to do with preventing premades, it only had to do with “unfortunate behaviors” of 30 people dropping queue and leaving the Alliance undermanned at the start of AV. This is why they removed numbers from the queue pop and prevented AV from starting without 20 players.
The new method of doing a premade no longer has this “unfortunate behavior” because everyone is required to take the queue and join the battleground to see which number they got into. No games start empty because of premades, and no “unfortunate behavior” (e.g., in the post-patch Horde meta of camping multiple graveyards and the cave without capturing any flags for 30 minutes) is occurring by Alliance premades.