Weavile (and the other spread decks, to an extent) aren't really in dire need of extra space. In all the spread decks, I think the advantage gained from being able to power up your finishing Pokémon in 1 turn is more valuable than the extra 2 slots you receive from using Tapu Lele.
Bronzong is a Stage 1 that requires DCE. It's already tough to find DCE for Tapu Koko, finding another for a Bronzong that gets softened by Po Town isn't really viable.
Similar to how Garbodor is so good right now because of how many abilities are being used, Weavile is also in a spot to deal a lot of damage. Nearly all decks play 1-2 Tapu Lele to the bench each game and Octillery/Oranguru are common nowadays. If there are just 2 Pokémon with ability on your opponents board, Weavile is matching Tapu Koko's maximum output for just 1 colorless energy and often times, Weavile can match Necrozma's damage turn after turn. Additionally, Weavile spread doesn't play any Pokémon with abilities, except for maybe a 1-of Necrozma-GX, so the 'recoil' from it's attack isn't much of a problem.
Finally, unlike Bronzong (or Zoroark-GX), which worsens the struggle to keep up with DCE attachments, Weavile can be powered up in 1 turn with basic energy, resulting in faster and more consistent spreading and pressure.