What was wrong with the floor-mounted dimmer switch? Remember? Well, maybe you don't. Like carburetors and cars without air bags, the floor-mounted dimmer switch has been gone for something like 20 years now. It has been replaced by The Stalk - that tree limb-like protrusion you pull back on to get the high beam to come on (or turn off).
This is supposedly "safer" and "more convenient" than the old floor-mounted dimmer switch - but that's debatable.
One problem with The Stalk is that actuating (or de-actuating) the high beams requires that you take your left hand off the steering wheel. In a tight turn, this can be awkward at the least - dangerous at the worst. One hand on the wheel is usually no problem when the car is pointed straight ahead; inertia tends to keep everything on track. But when the car is cornering, more steering effort is required; if you don't keep a firm grip on the wheel, it will tend to wander - and along with it, the car.
And that becomes more likely with just one hand on the wheel - even if it's only for a moment. It doesn't take long to cross over the double yellow line - and straight into oncoming traffic - when the car is traveling at 45 mph.
Another problem with The Stalk is that, unlike the old school floor dimmer switch, it is often the case that more than one function is involved. The Stalk may also control the windshield wipers (and washers) for example. It can be very distracting to suddenly have your forward view obscured by frantically waving wiper arms - and fluid spraying all over the front glass.
I drive a different new car every week and this is a fairly routine experience. If it's not the wipers coming on, it's some other function. The automakers have incorporated so much clutter onto not just The Stalk but the other controls and buttons they have grafted onto or near the steering wheel that it is quite easy to inadvertently trigger something you didn't want to turn on (or off) when all you wanted to do was dim the high beams.
So, what was wrong with the floor mounted dimmer switch? The functionality seems not just intuitively superior (simply tap you left foot to activate the high beams; another tap to return to low beams) but much safer since turning the high beams on or off doesn't force you to take one hand off the wheel - or inadvertently turn something else on, such as the windshield wipers.
I suppose that in a car with a manual transmission, there is the issue of "multi-tasking" the left foot, which has to engage and disengage the clutch as well as deal with the dimmer.
However, it seems to me that most high beam situations are not situations where much gear changing is happening. For example, long-haul Interstate driving. You're already in top gear, usually - so there's little worry about having to de-clutch and activate the dimmer at the same time. And if you are in a situation where frequent up and down shifting is necessary, you're typically in a high-traffic area where there is plenty of light anyway - and too many other cars to use your brights, regardless.
The floor dimmer was used without incident for many decades - from the '50s through the 1980s. Then someone had a better idea. Or so they thought.