When we work with mods, we understand how files work within the game (not completely, of course). In the case of reflections, they only "REFLECT" what is already happening on the court (Arena Lights and dornas).
This remains identical in 2K24, meaning the graphics engine continues to send and use the same information.
But when something is changed on the court floor, 2K changes a special file, and it contains the values of how much the reflections will appear. On PC we change this from 1% to 100% and it has NOTHING impact on the FPS, because as I said, stadium lights and dornas work regardless of this.
The frame drop problem is another error, it has no connection with this. In fact, I have 2K23 on Series X and Playstation 5, on Playstation, the problem almost doesn't exist, on Xbox it's aggressive.
As for why 2K would do this? Obviously I don't have that answer, but we've seen it happen many times, they always do it.