Why? Do we also need a strong Oklahoma and Iowa State and Clarion? We've done ok without them.
Wrestling needs strong programs where the sport will draw the most attention. Long-term, there's no compelling reason why that must be Iowa over lots of other schools. It's a smaller state with another major in-state school competing for attention. (Same for OKST.)
Rutgers, Ohio State, and Illinois are major schools in much larger states with strong wrestling cultures, and with no real in-state competition for attention.
Several other schools meet 3 of those 4 criteria: Michigan, Arizona State, Indiana, Maryland, Missouri, Wisconsin, Minnesota. (Admittedly, a couple would be harder pulls because the wrestling culture isn't as strong. That's on USA Wrestling to develop the culture.)
PA has enough population and a strong enough fanbase to support multiple strong teams -- Pitt and Lehigh at least.
Iowa has brand recognition, which is great, but so does Nebraska Football.