From the oral arguments it was immediately obvious that Alito and Thomas had already decided their opinion --- as had the other judges, frankly. They were very skeptical of the ByteDance/petitioner's argument. The Act at issue was written in a very specific way to neuter a lot of their points. Elizabeth Prelogar, representing the US Government, is also an extremely good SC lawyer in oral arguments. A Per Curiam decision is not surprising at all, most people who follow the court were expecting it.
From the oral arguments it was immediately obvious that Alito and Thomas had already decided their opinion --- as had the other judges, frankly. They were very skeptical of the ByteDance/petitioner's argument. The Act at issue was written in a very specific way to neuter a lot of their points. Elizabeth Prelogar, representing the US Government, is also an extremely good SC lawyer in oral arguments. A Per Curiam decision is not surprising at all, most people who follow the court were expecting it.
I think it is often the case that the justices' opinions are already established, based on their lines of questioning.
In the way that Gorsuch wrote a separate concurrence, I expected Alito or Thomas to want to broadcast a particular message to their audience.