That isn't as big problem as you paint it. Yes, Trump was particularily "lucky" (for the lack of the better word) that during his single term in the office 3 Supreme Justices died, so he could appoint replacements. But Obama, George W. Bush, Clinton, George Bush senior, they each appointed 2 Justices. So it seems to me that the system is deliberately designed to capture long-term political trends - Democratic presidents appoint democratic judges, Repliblicans appoint Republicans, and the net result is: Supreme Court reflects society's deeply ingrained values, not its current mood.