Every time you take a flight, for somewhere between 3 and 20 hours, you're told exactly where to stand, where to sit, what you can and can't wear, what you can and can't carry.
On the other hand, it no longer takes months to travel West and half your family generally doesn't die of dysentery on the way there.
Most people were merely moving from house to house, sometime town to town. It was not frequent, and everybody knew it would take time so there was not that much time pressure.
Today, a lot of people are expected to be able to travel hundreds of miles, regularly, in short period of times, with not that much rest between those times, and be on schedule. Schedule that is precise to a few hours.
Appart from nomads and a few merchants (again traveling a way slower pace, frequency and lower expectations), most people just stayed put.
You for a cross continental trip you lose days of your life confined to the interior of your car. I'd rather suck it up for a few hours and kick my feet up at the destination.
You are only confined when the car is at speed. There are ample opportunities to stop, exit, walk around freely, relieve yourself in a full-sized, accessible bathroom, buy food and drink at normal market prices, and even visit points of interest. Pets tend to be more comfortable, and you don't require a specific carrier to travel with them. Seats recline to a comfortable angle, and there is usually more legroom in a car.
While you are moving, the speeds are far lower--70 mph rather than 350-550 knots. The safety factor is lower; you're more likely to die in a car wreck than a plane wreck per distance unit.
But there's also no security queue or baggage check for a road trip. There's no airport ground transportation. There is a form of check-in for seat determination, but online and other early check-ins are specifically disallowed by the "shotgun rules". You save a fixed amount of time per trip with car travel, while airliners save time based on total trip distance.
So for me, airline travel beats car travel only beyond a certain distance threshold, which more or less directly equates to the travel time. I now set my threshold at two days. If I can't drive there within two travel days, I fly, or just don't go. Which means I'm now potentially adding hotel room charges to mileage expenses. That's about a 1000 mile radius for "easy" driving days and 1600 miles for "hard" driving days, which require relief drivers.
This is directly driven by my perceived worsening of the air travel experience. Sorting the customers out into service tiers based on how much they spend does not encourage me to spend more or to be loyal to a specific airline. It encourages me to pursue alternatives to the bad service that I know I will get.
On the other hand, it no longer takes months to travel West and half your family generally doesn't die of dysentery on the way there.