Yeah, “ackshually it’s a republic” is usually a case of midbrow “incorrecting” (political scientists regularly use “democracy” to label a basket of political systems that include democratic republics, it’s not just normal vulgar usage, the “pros” use it that way, too, all the time)… buuuuut this time it might be a hair worth splitting.

I don't think the meaning of republic changed, it just got conflated with democracy because we often say 'Democratic Republic', which requires at least in modern (18th century and beyond) terms that the common people vote to decide political direction or policy.

The US itself didn't start off very democratic, and could have stablized into a more oligarchic nation if it kept the notion of only allowing property owners to vote. Originally, land ownership wasn't a high barrier of entry, but in a more modern era corporations or oligarchs could own most of the land, and lease it out to prevent anyone else from gaining a vote.