My gut feel is that people drove very badly in the before-times but often also very slowly and cautiously at the same time. Speed felt dangerous in old vehicles. Modern computers with wheels are like living rooms with great acceleration and decelaration. Maneuvers which would had taken great skill to perform with an old rear-wheel drive car with bad tires, are now executed routinely like it's nothing, thanks to antispin, traction control etc etc.
Cars are much safer now, especially on the inside, but when you get hit on the outside by a several tonne projectile, it's about the same as it ever were.
this is definitely a big part of it. in the past, cars were either small with tiny engines or big "boats" with massive engines and super soft suspension. those old suspensions weren't really about control - they were for comfort or just trying to deal with all that weight. now basically every car, no matter the size, comes with lighter parts, way smaller but way more powerful engines, smarter computers, better tires, and most importantly, way better suspension. all that means a lot more grip, way faster acceleration and braking, and a much bigger feeling of control - even for people who might not be paying full attention (or really know what they’re doing).
we've kind of made every car a sports car, and that means when people make mistakes, those mistakes get out of hand way quicker before physics wins.
then there’s the whole manufacturer's arms race - the classic prisoner's dilemma. trucks and suvs just keep getting bigger, faster, heavier, packed with screens and gadgets. all the old luxury stuff is standard everywhere now. so everyone is more and more isolated from the actual consequences of bad driving ... until they're not.
Cars are much safer now, especially on the inside, but when you get hit on the outside by a several tonne projectile, it's about the same as it ever were.