I think the concept of an Overton window doesn't work well with our modern politics. The window hasn't really slid left so much as split in half and slid both left and right.
The far right now says and does things that would have been completely out of the Overton window three decades ago, as does the far left in the other extreme. It's like there are two Overton windows depending on which wing you associate with, which is why increasingly people find that they can't engage with those on the other side at all—they're operating with different windows of acceptable expression.
The far right now says and does things that would have been completely out of the Overton window three decades ago
This just seems like projection by the left who don't want to admit that they're the only extremists doing insane things in America. The left will make an extremist claim - "men can be women" - and then when the other side says "no", they'll claim that the right is being extremist for opposing their own extremist claim.
The far right now says and does things that would have been completely out of the Overton window three decades ago, as does the far left in the other extreme. It's like there are two Overton windows depending on which wing you associate with, which is why increasingly people find that they can't engage with those on the other side at all—they're operating with different windows of acceptable expression.