My team got split up recently, and I got put onto a sub-team I'm less familiar with (I have more context and experience with the other sub-teams formed in this re-org). Any thoughts on how I can make a case to be on one of the teams I feel like is a better fit for me, and if I'm not able to do that, how do I make the most of this new situation?
If you feel really passionate about the other team or think you have some unique knowledge to contribute there - best is to just talk to your manager and say whatever the reason is in a very mature way. It is both helpful for the company and manager if you are working on things that you are passionate about. No manager wants people on their team to be working while being unfulfilled.
Having said that, I recommend you to see it as an opportunity to work on something else, people who do really well are resilient and can quickly accept and adapt to the new situation. In big tech, such changes happens all the time, this would be a good opportunity to build the muscle of resilience.
Overall, I say approach the whole thing with a lot of emotional intelligence and maturity, it is fine to talk to your manager but if a change can't be made - accepting and adapting to the situation shows highly on you.
First, I recommend going through these 2 resources: