” They exchanged the rule of law for the rule of the majority. “
No. Not even close. Rome NEVER was a “democracy”. They were a Timocracy that ended being an oligarchy.
I read some of John Adams’s papers on the Roman Republic which was very much an oligarchy long before the republic ended. The patrician ruling class served itself very well. The only sense of democracy I could see from both Gibbons and Adams was the power of the mob if it was assembled and directed to action by one or more patricians. Some patricians used the mob effectively to kill a rising and popular figure among the people. The mob turned against this popular hero when they manipulated by the patricians. Threw the poor fellow over a cliff and onto an infamous rock (name escapes me).
Bottom line however, except in the very earliest days of the republic, there was no democracy up to the end, west and east. Roosevelt get that wrong.