Yes, Howard had a Remote Kissing Machine. https://www.youtube.com/watch?v=M9KXKbBKp1A

You seem to be assume the use of integers to identify the rooms. And there are many alternatives to linked lists.

A simple method would be to generate a pair of unique strings for each entrance/exit of a room. The first string would identify the current room / board, and the second string could represent the destination room. If you want to get really interesting, you can have one-way doorways, or even a different destination based on various factors. A simple hash table or an indexed database table could be used to locate the rooms. If the target string doesn't have a room associated with it, then you create a new room, save it, and then load the new room.

Just because an exit from one room takes you to a previously visited room doesn't mean the world repeats. In fact, if that never happened, the game would be boringly linear.

There is no reason that the entire world has to be in memory at one time, only the rooms where players are located. When memory gets tight, you can page out any rooms that are now empty, or perhaps where there has been no recent activity. When a new room is loaded, you can control its contents based on if the player has been there before, or if this is the first time that any player has been there within some time period. That would allow some one-time objects, others to be regenerated periodically, other items to be limited to one per party, etc.

I remember reading similar concerns when PBS came out with a radical new TV program called "Sesame Street." ;^)

It is much easier asking these questions than doing actual research and coming up with some answers. I think a lot depends on what they are doing with technology: if they are reading and learning or just goofing around and wasting time.

I taught college classes for a number of years. Eventually, it became very common for students to bring their laptops with them to class. Some of them followed my lecture notes and tried sample problems. Others read email, web sites, or played games with the sound turned off. As long as they weren't disruptive, I didn't try to stop them.

Of course, K-12 is very different than college, but when I was in high school, I carried a book with me to read when a class got boring. These days I carry several books on my phone in case I get some extra time. My grades were pretty good, so I didn't seem to suffer from not paying attention.

Essentially, the question seems to be: "Does the teacher have to keep the students entertained?" Perhaps it should be phrased: "Does the teacher have to keep the students involved?" Teachers that drone on endlessly, sometimes reading their lecture notes, will have problems. Those that interact with their students and have activities that involve the students will do much better. As always, anything that changes the current situation is suspect.

Not only did I get an Ovaltine secret decoder ring, but I made my brother drink it, since I couldn't stand the stuff. ;^)