I travel by train a lot here in the Czech Republic and I have racked over 1 million kilometres by rail in my lifetime.
My most consistent pain point when changing trains is the uncertainty about the delay and whether the connecting train will be waiting or not, how far is it going to be (it may be on a very distant platform and platform use isn't consistent even on the same railway station, much less in different regions) and whether I will have to run even with a heavy baggage and/or pain in my knee (which I sometimes have).
Delayed direct train just means you'll be a bit later in your destination. Delayed train with a missed connection may mean 3 more hours in the railway station or even a necessity to stay overnight in a place you barely know.
With rail, as usual, it depends. Connecting between bigger cities is easier, some countries make things particularly difficult. Most of my train experiences are on metro or commuter rail, most of the longer trips I've done were direct. German (DB) stations were generally easy to navigate and staff were universally dour, but travel itself was relatively painless. Berlin (Mitte) to Amsterdam airport at night? No problem. UK? You learn to just lean back and think of England. The Tube is great and relatively easy to route around closures, GWR is an expensive fucking shit show.
I've spent more time flying than doing long-distance rail trips and yeah delays happen which is why I pick connecting cities carefully. I'd much rather be stranded in New York than Atlanta or Houston.
But cars bring all sorts of uncertainties too. Let's say it starts snowing and you don't have chains (oops) or the roads are closed. Yep you're gonna get stuck for a while.
This past Wednesday I went out to what I always thought of as a semi-remote beach (about 25 miles away from home) to catch the sunset. After that was said and done my car wouldn't start. If I walked a mile back to the beach in the dark I might've been able to find a spotty signal and text for help. I decided to sleep in the car, and when the sun came up I walked ~6 miles to the nearest state park and then another mile or so to the ranger station. About half way there I got a signal for long enough to get cat pictures someone texted me the night prior, but for some reason my carrier decided to block outbound messages "Unable to send message - Message Blocking is active." The park wasn't open so I wandered around until I found someone who offered to give me a ride into the nearest town with a tow truck. A few hours later I was in the tow truck, on a two lane road, on my way home and traffic in the other direction was at a standstill. Someone had run their car off the road and judging by the number of cars waiting they'd been waiting for a while. I took that in stride but that would've been hell with kids. If I didn't know that area was low crime I would've had to schlep all my stuff into town.
My most consistent pain point when changing trains is the uncertainty about the delay and whether the connecting train will be waiting or not, how far is it going to be (it may be on a very distant platform and platform use isn't consistent even on the same railway station, much less in different regions) and whether I will have to run even with a heavy baggage and/or pain in my knee (which I sometimes have).
Delayed direct train just means you'll be a bit later in your destination. Delayed train with a missed connection may mean 3 more hours in the railway station or even a necessity to stay overnight in a place you barely know.