That's awful! It would explain recent lack of big vassals in the HRE in my games and its meltdown due to emperors rarely disposing of a significant power base of their own demesne.Wining the HRE election for one character is very punishing right now:
1. Your elector title (titular duchy) is automatically destroyed
2. Titular kingdoms always pass on to the emperor, even if they had a non-elective succession before
2. You lose any non-de jure vassals, regardless of previous points
Is it really meant to work like this? It's probably the same for any elective realms, including MRs