"What if" transfer question

Hey everyone. So I graduated college about four years ago from a middle-tier Big10 school (think mid-west, but not NW, UM, Wiscy, or IL). Very good school, had a great time, did very well, no regrets. However, I’m reflecting on my college career and am just thinking about if it had played out differently.

I was very smart as a kid (high IQ, gifted and talented programs, etc, was actually smarter than some of my friends who went on to Ivy league schools/Johns Hopkins), but I got very lazy in HS, and it affected my college admissions cycle. However, I got my act together again in college and ended up graduating Phi Beta Kappa. My GPA was very high in school and I did toy with the idea of transferring up a level both after my freshman and sophomore year (GPA was a 3.87 at the end of my soph year). I don’t regret staying at my school at all, and have been accepted into a great grad program, so you can say things have kind of come full circle for me. However, I keep wondering what my ceiling would have been as a transfer student, and if I would have cut it at a truly elite university.

Given what my GPA was at a reputable Big10 school, if I had decided to transfer after my sophomore year, what do you think would have been the probability of me getting into some of the elite universities in this country, such as the Ivies, U Michigan, Georgetown, Notre Dame, etc.? I know that schools also require test scores from transfer students. My SAT score was pretty average at 1150/1600 (old SAT format, did not do much prep work…). Appreciate any feedback. Thanks!