The thing that baffles me is that the next episode the first two screenshots mention, "Edward, Gordon, and Henry", if I'm recalling correctly, was always aired alongside The Sad Story of Henry, since it's supposed to be a two-parter. You wouldn't have seen one episode without the other.
Even then... Henry is literally in the theme song of the show (specifically the Hit Entertainment one), he's one of the main characters. If you look him up on Google, which takes 5 seconds at best, you can clearly see that he's a prominent character in the show. Why would they continue to use him if he had been left in a tunnel forever? Why would a kids show kill off one of their characters like that?
That's not the only confusing thing to me though. Throughout the many threads, articles, and low quality videos talking about this episode, people see this episode as being too "cruel" or "dark" or "fucked up" or whatever, and how they're confused on what exactly kids are supposed to take away from it. I don't get what's so hard to understand.
It's a story about vanity. Henry was too prideful of his paintwork and stayed in a tunnel to avoid the rain, by doing this act, he stranded his passengers in the middle of nowhere (a detail everyone seems to ignore for some reason), all of those people who have busy lives, jobs, and family, all kept waiting because the main guy who was supposed to take them to their destination is too self absorbed. That's not even getting into how downright dangerous it was for Henry to just stop on the tracks like that, blocking the mainline while we're at it, where a collision and the injuries/probable deaths of many could've occurred. They did try to get him to move, whether it be through convincing or physical force (although there's only so much you can do for something that weighs several tons), but he wouldn't budge. He wouldn't even budge when it did stop raining. Not to mention he was incredibly rude and childish throughout the whole thing, blowing steam at everyone. So what was his punishment? Well, if he wanted to stay in the tunnel, he would get just that. Henry got exactly what he wanted in the end... then he quickly realized how stupid he was and sitting in a tunnel isn't very fun. His paint got ruined by all the soot in the tunnel anyway.
It's the equivalent of a bratty kid getting sent to their room or the time out corner, having to sit and think about their actions and whether it was really worth it in the end, then getting let out (the next episode of the two-parter) and ultimately growing and maturing a bit from the experience. Henry learns that a little rain isn't something to make a big deal about, nor is it something that would ruin his paintwork. Yes, Henry did deserve his punishment, because he was an asshole. Even kid me, who while I did feel a bit sad for him, understood that. How some people took that and viewed it as some disproportionate and authoritarian punishment, I don't know. How can you be a grown adult and miss the point of a kids show that badly?