I went there in the late 80s and early 90s! It has quite a history. Maybe a bit of a party school, but that was easily avoided. It was known for having a large international student population. I don't think it still does.
It has a large school of technical careers that has programs in aviation, automotive management (managing fleets, etc.), mortuary science, etc. But it's also a research university.
I don't know what it's like now, but I would check it out. The town of Carbondale is very Democratic, like many college towns. Downtown is a short walk from campus and there are the usual bars, restaurants, theater, etc.
I studied Russian which I think they no longer offer. I still remember my gen ed Philosophy professor and Russian History professor for being amazing. It wasn't perfect, but I have great memories.
But now SIU has half the students as when I went there. Here's an article about it and how they are fighting to maintain standards of DEI. I don't even recognize the school in the article. I never thought of SIU as having basically only local reach. There were people from all over the world doing their research, and undergrads from all over too, including tons from Chicagoland. And rural America leans to Trump everywhere, not just the countryside around Carbondale.
So maybe they are trying extra hard now to recruit. That can be good. I would research specific programs.
https://www.propublica.org/article/regional-public-universities-trump-funding-dei