Note that 1.19.0.33 preview is actually called 1.19.0.66 on Xbox for some reason, but replicate the bug use a Xbox series x and open Minecraft preview version 1.19.0.66 and then open another game and then go back to Minecraft preview version 1.19.0.66 using quick resume and the framerate should be above 60. The only way to fix it until you quick resume again is to close Minecraft preview completely.