nickaix posted:More than annoying the old hands, they confuse new hobbyists. We don't need more words with definitions which change based on the context.
Good point and well understood.
Now I would venture what should we call the more finely detailed rolling stock?
Well, I guess I have proved the adage that it is always easier to complain...
Probably, it is just best to say exactly what you want...and I see you have changed the thread title to do just that.
Ever since the '70s, Lionel has used "Standard-O" to describe their top-of-the-line, 1:48 scale pieces. The trouble is, top of the line is a moving target. The first car you posted is a Std-O car from the late 90s, and was at the top of Lionel's line at that time. It doesn't hold up well today. So, if buying Lionel marked Standard-O, you need to know when the car was made. A good rule of thumb is to avoid anything with a 17*** number, since most of these were made pre-2000 and are therefore less detailed.
I notice that the last couple of catalogues have dropped the "Standard" designation, and now just distinguish "O scale" from "Traditional". I suspect that everything in "O scale" should be acceptable to you, with the exception of the LionScale line. Those are mostly made from older Weaver molds, and do not have the same level of added detail. Interestingly, the ACF 3 bay covered hoppers in this year's LionScale line are Lionel's own models; when these were introduced in the late '80s, they were considered Standard-O. But they would not be good enough for that category today, so they have been moved down to LionScale.
You will even see a former Std-O car offered in a Traditional line set from time to time. But you can bet that, if it is in that set, it is because it is no longer state of the art, so pass it by. MTH has done this too, as you found out, with some of their former high-end O scale product being reincarnated as RailKing.
Hope that helps some!