this is a fallacy my team has been talking about for 20 years.

https://www.rangevoting.org/IRVsplitExec.html

tl;dr IRV is extremely poor, doesn't actually solve the vote splitting problem, and is radically more complex and cumbersome than superior alternatives like approval voting, which would plausibly scale far faster once gotten off the ground. plus approval voting was adopted by 2/3 majorities in fargo and st louis, so we know it's politically viable.