I’ll start with the Porsche 997, the 996 looked alright imo, but it looks “like a 90s Porsche”, the 997 made it look sleeker and more modern. Still looks good today.
As for cars that looked worse after a facelift? Maybe the facelifted 6th gen Camaro? The 6th gen looked great pre-facelift, but they did something weird with the headlights and now it looks so-so…
As the owner of a 2016 Honda HR-V, I think the 2019-22 models are horrid. Those chrome-looking grilles look dirty even when clean.