The closer the game holds to reality(and nobody is expecting the game to mirror reality), the more realistic it is. There isn't a person alive who has every circumstance they encounter meet some sort of personal dramatic need. Games that are all about meeting dramatic needs, while fun for those who play they, are inherently less realistic on that aspect of RPGing than simulationist games where sometimes a dramatic need is met, and sometimes it's something else.
Here are two scenarios.
1) The PCs leave town, traveling to the north and run into goblins.
2) The PCs leave town, traveling to the north and run into the tribe of orcs that killed the ranger’s family.
Which is more realistic?
I'm not talking about the passion-project types, I'm talking about the big players - WotC, Paizo, a few others.
But WotC doesn’t make more than one system. And Paizo doesn’t really, either, with Starfinder as an exception (though I don’t know if they’re even still putting out material for it).
Most of the big companies produce games based on one system. So I’m not really sure if your initial point is all that valid.
There might not be a direct translation but IMO there's at least some correlation between length and quality, in that a longer campaign is more likely to entail deeper and richer interaction with the other characters (as they come and go) along with the setting and its elements; if for no other reason than people tend not to begrudge the time these things take.
Nope, it’s a preference. If it’s a preference a person has, then they may be more likely to consider a longer campaign yo be good. But, I’d think that if a campaign is good, it’s more likey to go long because the participants are enjoying it. The length of a campaign would, in that sense, seem to be a result of the quality of play rather than a cause of it.
Also, deeper and richer interaction with the characters doesn’t seem to be about length of the campaign so much as the game’s focus. I’ve played years-long campaigns that had very shallow and minimal character interaction. It doesn’t tend to be what the game is about. There are games that are designed to be focused specifically on the characters and the depth of their interactions.
Given how often you seem to criticize this kind of play, it seems strange to now see you claim that its goal is a positive outcome of long campaigns.