This is basically what played out in the 20 years that I've been an adult. https://i.nostr.build/zdvVz.jpg
That's been my experience of it.
I'd argue it is worse than that. The right and the center people have all moved left. The left has just moved farther left. JFK was a liberal super star in the 60s. He would be right of at least 60% of Republican Congressmen and maybe 90% of them, today. People don't realize how far we've moved. Maybe I can see it more because I've been around longer.