Jumped the shark? Definitely not. I’ve liked all the new Star Wars movies, even Rogue One which had many problems (mostly with characters), and The Last Jedi might be my favourite of all the films.
I do think, however, that it’s become a very saturated franchise. Even now I’ve lost most of the anticipation for the new films. The Force Awakens was easily the most excited I’ve ever been for any movie ever, but each conesecutive film I’ve been less hyped for. Not because I think they’ll be bad, just because there’s have been four movies in less than four years.
If they retain the level of quality they currently have, and return to releasing the films every three years, that’d be perfect, for me at least.