Vince McMahon runs WWE as he sees fit and for him, superstars being able to speak English properly is very important so that they interact with the English-speaking fans, which make up the majority of the WWE Universe.
Andrade was in a rough patch for a while but it seems he has gained momentum. While he has Zelina Vega as his manager who can do the talking for him, he still has to talk himself.
Fightful reports that Vince McMahon is high on Andrade right now. Andrade’s English has been improving as of late and this could be why he has been given a push. After all, his first English language promo wasn’t all that good.
WWE Superstars need to be able to speak clearly as well. This is especially needed when they perform in buildings where the PA systems aren’t all that good.