#3 The momentum of his character

One of the major things that WWE has gotten wrong several times over the years is that they tend to fail to capitalise on superstars' momentum, especially when they're really hot and over.
To their credit, that is something that has reduced quite a bit in 2018 and especially 2019, with WWE clearly capitalising on the hottest superstars - as seen at WrestleMania 35 with the likes of Becky Lynch and Kofi Kingston.
Cody has no chance against John Cena? Details HERE
With that said, one can only hope that their record in 2019 continues and they're able to give Wyatt continual momentum. They've been very smart with the way they've handled him - only making him appear occasionally for his attacks.
Moreover, the fact that he's hardly in the arena itself gives him a very special feel and WWE knows that he's not the kind of character who should be wrestling on RAW every Monday Night. He's a special type of character and by carefully pushing and protecting him, they've managed to give him a lot of momentum that he lost by the time he was last around in 2018.
The main reason why WWE would want to push him to a Universal title shot is to keep his momentum going and have him become stronger than ever.