Sheldon (Jim Parsons) is currently happily married to Amy (Mayim Bialik) in The Big Bang Theory, but he may have been better off had he ended up with his Texas friend, Paige, instead. Played in Young Sheldon by McKenna Grace, Paige was introduced in the prequel spin-off's second season as another child prodigy in Dr. John Sturgis' class. Like Sheldon, Paige is highly intellectual but is more well-adjusted than the titular character. While Sheldon views her as a rival, she doesn't seem to mind the competition, and even befriends Missy. She may have only appeared in a handful of episodes in the offshoot, but she seems to be better-suited for Sheldon than his current wife.
Introduced after she's chosen as the most ideal partner for Sheldon by an online dating platform, Amy immediately made a connection with the eccentric theoretical physicist for sharing the same quirks, not to mention having the same mindset when it comes to a lot of things. Over the years, the two developed a romantic relationship despite both initially denying their attraction to each other. By the end of season 10, Sheldon finally got on one knee and asked Amy to marry him and, after another season, the two tied the knot with Mark Hamill officiating. But while the couple has been doing well as newly-weds - even being up for a joint Nobel Prize for Physics - Sheldon may have found a better life if he'd married Paige.
When Amy first debuted, she was positioned as the female version of Sheldon, which explains how easily they were able to find a connection. By sharing the same wavelength, they can be fully themselves without any judgement from each other - and for a time, this was the case. At this point, fans fell in love with the idea that Sheldon finally met his match, and it took a bit of time before they finally realized that they're perfect together. But throughout the years, The Big Bang Theory has started to normalize Amy, losing the sense that she's Sheldon's counterpart.
Oftentimes, Amy is the voice of reason in their relationship, further alienating her husband as the only truly eccentric member of the Pasadena gang. Despite that, she lacks the conviction that needed to straighten out Sheldon when he's truly being unreasonable. She's head-over-heels for him, and that usually clouds her judgment when it comes to her husband's behavior. Granted, Sheldon has exhibited social growth the past few years mainly because of her love for Amy, but we can't help but wonder what would've happened to him if he married someone who holds him truly accountable for his actions as a fully-grown adult.
Not used to having someone as smart as he is, Sheldon is irritated with Paige - especially since she makes good counterpoints that he's unable to shoot down. She challenges him intellectually in a way that humbles him. While Sheldon dislikes dealing with her, he doesn't seem to hate her enough to drive her away. It’s too early to tell if their relationship will eventually lead to something romantic, but if Young Sheldon heads this way and in an alternate reality, crosses over to The Big Bang Theory, we can imagine that Sheldon will have been better-adjusted compared to how he currently is. Unlike Amy (and Sheldon's mom, Mary) Paige would've called him out on his rude behavior, instead of giving him a free pass simply because he's "different." If Sheldon ended up with Paige, he would’ve been forced to mature way faster because she wouldn’t enable his obnoxious attitude.
It's still early to tell what would happen to Sheldon and Paige, but at this time in Young Sheldon's narrative, there are still no signs of Paige leaving, which means that we'll see her with the show's titular character for a while. It will be interesting to find out what happened to her, and why she's no longer part of Sheldon's life.
The Big Bang Theory and Young Sheldon air Thursday nights on CBS.