There's a lot of issues and there's a lot of nuanced factors. I can't even begin to cover all the ones I know about, let alone know them all.

High up in politics there is no meeting in the middle, the other party is the enemy. You're in the club or outside of the club, that's it. That same attitude trickles down to workplaces and social circles. If you want to work with the other team you get put on the sidelines, minimized, have your funding cut, miss out on a promotion. It's essentially join or die, and often times you see people throwing death threats at the other side online where they presume they are anonymous.

Then there's Education. It's mostly dogmatic. It's not about teaching life skills, it's about teaching people to be good workers and to follow along with the status quo with a sprinkling of whatever political ideology runs the state/town. That doesn't help, but changing any of it is highly political.

Universities tend to be liberal, and the highly conservative jobs tend to not require those degrees. You can be a master electrician right out of vocational school, why would you go to a university? If you do have a four year degree, why would you want to work in construction where the environment is so much rougher?

Plus there's the gender gap...

Too much nuance for a comment on social media. This is already way too long. I see no way to fix the system either given that changes need sponsorship by the ones who benefit from the system today.