@B P (Ult1m4) Republics have fallen in the past, and they will again. Despite that I think they're better to live in, the cycle of history doesn't care.
Rome printed money until it stopped working too. Also attempted price fixing. Eventually, the economy doesn't hold up any longer due to corruption and waste. The public finally considers the ruling class illegitimate. The military or whoever has the most military force sees it as an opportunity. The details after that can be relatively fortunate (still bad, but less) or awful.
Just as kings were untouchable until they weren't, so too is the ruling class under an increasingly corrupt republic.