No they didn't last long did they. It was communists in Bavaria that forced the King there to flee for his life during the initial revolution. Afterwards the Bavarian Royal family were able to come back and remain popular and respected, to the extent that there was a very real possibility that Rupprecht could have been reinstated during the thirties, as opposition to Hitler. Apparently there was a lot of very real support for the idea, including Rupprecht himself, yet the Bavarian Premier(?) could quite muster the courage to do it. (Not sure if that was because he was afraid of reprisals from Hitler or if he was a determined Republican who couldn't quite accept the idea.)
Kaiser Wilhelm II. was really popular until 1914, then he was despised and after 1918 and the abdication he just was forgotten. I've never heard my grandparents or great-grandparents speaking about him and I was always interested in history.