In Develop mode, when I move my cursor to a preset name and click, I can see it apply to the image, then as soon as I move my cursor away, it goes back to the raw image, and the preset won't apply. However, the profiles will work on the right-hand side when used from that panel.
On a Mac, running Lightroom Classic 11.4, have removed and reinstalled it.
Have checked the preferences and I'm not storing the presets with the catalog.
The preference file can get corrupted leading to buggy behavior. A corrupt preference file will survive uninstalls, updates, and upgrades. By renaming or moving or deleting the preference file you create a situation where LrC will recreate a fresh new one upon startup of LrC. Be aware various settings will revert to defaults.