Warning! Spoilers ahead for Young Sheldon's 100th episode.
The 100th episode of Young Sheldon ruins its heartwarming tribute to The Big Bang Theory finale. In 2019, after 12 seasons, the nerd-centric sitcom wrapped up its run. Surprisingly, The Big Bang Theory's ending was satisfying for many, and it was made much more special with Young Sheldon's homage. Now, however, what's initially a touching send-off doesn't feel that much special anymore.
While they exist in the same reality and share the same lead character, there was barely any narrative connection between them when Young Sheldon began. But when news of The Big Bang Theory got out, CBS actively tied them together, staging an unconventional crossover, as well as, the appearance of Tam (Robert Wu), Sheldon's Texas best friend in The Big Bang Theory. In the end, Young Sheldon honored its parent series with season 2 finale that references Amy (Mayim Bialik) and Sheldon (Jim Parsons) winning the Nobel Prize.
The Young Sheldon season 2 finale covered the surprisingly heartbreaking plot of Sheldon throwing a Nobel Prize party, only to be distraught after no one showed up to it. As he sat there listening to the announcement of winners, the narration from adult Sheldon recalled how bad he felt that day and how lucky he is to have his Pasadena gang. The camera then revealed what the rest of his future friends were doing at that very exact moment. The whole sequence is touching, especially seeing the child versions of Leonard, Penny, Amy, Howard, Raj, and Bernie in their own worlds, oblivious to Sheldon's sadness. But The Big Bang Theory prequel reveals that the socially-inept genius didn't even have to wait that long to have his own friends. After his initial encounter with his dorm neighbors, Young Sheldon's 100th episode showed that Sheldon has both been spending time with them and actually enjoys being with them - making the Young Sheldon season 2 finale less impactful, as it shows Sheldon gained friends before meeting The Big Bang Theory's cast of characters.
Before Young Sheldon's 100th episode, there wasn't any additional indication that Sheldon continued hanging out with his dorm friends. Especially since the last time he spent time with them, he suffered a stomach ache because he got too excited playing retro video games and ate too much. But, apparently, they remained good friends, and it wasn't because the kids next door have any ulterior motive against their younger school-mate. In fact, it seems like they've genuinely taken him in and included him in their close group. This makes it curious why they were never mentioned on The Big Bang Theory. It seems the only way the show may be able to justify why Sheldon's new friends are never mentioned by him as an adult would be a potential fallout, and indeed this seems the most likely explanation, as Young Sheldon also used Sheldon and Tam getting in an argument to explain why that character was also never referred by the adult Sheldon.
As Sheldon continues his stint at East Texas Tech, chances are that he will continue to hang out with his dorm neighbors moving forward. The character's solo adventures in Young Sheldon season 5 have been mostly set in his school, separate from a lot of family drama. But considering the impending problems with George (Lance Barber) and Mary (Zoe Perry), it's comforting to know that Sheldon has good friends to lean on - even if Young Sheldon's 100th episode does dampen some of its ties to The Big Bang Theory itself.
Young Sheldon airs every Thursday on CBS.