The idea that rail travel is "difficult" is hilarious when you compare it with eyes open against plane travel. I avoid flying if I can, and I've had fabulous trips to many countries by train and boat. Some friends say "Sounds great, but I couldn't manage it from where I live. And with the kids too!" - I think they've blinded themselves to how much flying is a pain in the bum.
I had to go by plane recently, for urgent reasons. It's complex, weird and alienating, and there are lots of strange processes which are definitely more complex than a train timetable.
I was really surprised to notice how much walking is involved. Recently, we were at Munich train station. It's a big train station, and we said to ourselves, "Gosh, it takes about 10 minutes to get from our arrival to our other platform" -- but then while taking a flight recently I had to walk inside the airport for twenty minutes. At BOTH ends. Twenty minutes is not an exaggeration: I timed it. (I used the travelators. I had no baggage to collect. So this is a very optimistic version of how long it takes.) So, forty minutes of walking added on to the journey time, which is hidden away, pretended not to exist. It's hidden inside the "airport" ritual so we don't think of it as a separate task.
I notice the weirdness of plane travel in the phenomenon of these hard, wheely, rectangular suitcases that are now ubiquitous. They're useless for almost everything - walking around a city, for example - and they're much heavier and less adaptable than soft-cased luggage. But they're specifically tailored for airline cabin baggage size restrictions, and designed to be robust against throwing around on a luggage conveyor, and so lots of people buy this baggage, condemning themselves to be awkward in all situations except the airport.
In my normal travels I don't need to worry exactly what size or shape my bag is - I just bring as much or as little as I need.
I notice more weirdness when I go through airport security, of course. Unless you're a frequent flyer there's no way to keep track of the varying security requirements: on my recent flight "shoes off" and "laptops out" were not required, but "belt off" was -- and I've no idea why. In one direction, I had to show them my tootpaste tube. In the other direction I didn't. The absolutely yucky experience of those body-scanners is another horrid part of it.
The "overbooking" phenomenon is yet another bizarre aspect, which I think regular users take for granted... Sitting in the boarding lounge for the flight I've booked, with a seat number printed right there on my boarding card, I hear regular announcements "This flight is overbooked - if you're willing to take the next flight, for a cash reward, contact the desk." Clearly it's dumb for the airlines to deliberately overbook their flights: they do it to squeeze the maximum profit out, inconveniencing us with a mild dishonesty while pretending they aren't doing. Does someone else also have a boarding card with my seat number written on it? Wouldn't that be weird? What if no-one volunteers?
I don't need to say much about the strange upselling tricks they use during the sales process, pretty much a cliche. One airline wanted to trick me into paying extra to choose a seat; one wanted to trick me into paying extra for baggage. These "dark patterns" are well-known to people who do this, but gee it makes the whole thing complex to work out.
How is it that people put themselves and their kids through this weird business, and why don't they say "I'd like to fly for a holiday, but I couldn't manage it with the kids"? It's what you're used to, I'm sure. There's also a lot of commercial interest in it, as you can tell if you walk around the airport terminal surrounded by strange perfume adverts, trying to find a drink that is NOT a beer from the official sponsor's brand.
It's funny to compare this against my experience of train travel. There are some definite tricky parts e.g. how much of a gap to leave to make sure you don't miss your connection? (If you're changing trains in Germany, leave 30 minutes gap in case of the almost-inevitable ten-minute delay...) But the process is so free, and so NORMAL. You don't need weird luggage, or bizarre procedures. It's almost the same effort to get on a train across Europe, as to get on a bus to go down into town!