This is the bit that seems unlikely to me. In my experience back then it was mostly academically more able who where playing D&D, especially in the role of DM.
I had quite a few brilliant players who were LD and unsupported academically if not for BOCES technical classes. Special Education was a lot of throw them in a classroom at the end of the hall out of sight in the 80s in American education or label them behaviors and send them to vocational school.
True, I have learning difficulties myself, but was fortunate enough to get support.
In my experience that is only partially true. It also attracted artists and creative outcasts who hated school and who, in some cases, would rather play D&D than do their homework. In my larger gaming group, two of my friends ended up having to go the GED route. Neither were dumb. One was a very talented artist, but a stubborn non-conformist who just didn't give s**t about school. The other was a musician and theater type who was going through a lot of personal issues, including getting his girlfriend pregnant in his senior year. Both have gone on to do well enough in life, but high school was wasn't the best environment for them. I think this holds true for a lot of D&D players in those days. For some it was an escape.
This isn't a voluntary response. It is well documented as an involunatry response to perceived inconsistencies in fiction, and something widely considered in the creation of fiction. Making a concious decision to overlook an error is inherently impacting immersion as you shuld be 'lost in the story', not making concious decisisions.
Not sweating the small stuff applies to decisiding that you don't want to raise an objection or otherwise address a small problem. That is different than noting that the small problem exists. You can't decide not to sweat a problem until you notice it, and noticing it is what reduces immersion.
For you. Maybe for the majority of people (care to provide evidence of such?). But obviously not for me.
My grades in high school SUCKED. I was a slacker who barely did any of the work required except for the few classes that interested me. I barley had passing grades and was primarily the DM so while what you say may be generally true there are people like myself who were exceptions to that.
There was definitely a mix. Most of the people I knew who were playing were at least avid readers. In most cases, that correlated well with academic achievement - but not always. I DMed a lot and was my class valedictorian when I graduated - I was motivated to have a lot of college choices. But a good friend of mine also DMed a lot, was an avid reader and very intelligent, but just wasn't as interested in getting the school work done compared to doing his own thing. Drove his parents nuts. The best DM around when I was in high school, however, had some learning disabilities with math (he used calculators a lot when DMing), was primarily an artist, got middling grades in everything but art, loved to read Conan books, and he was a black kid who lived in the trailer park in a small town in Wisconsin.
Not everyone will have the same response to phenomena. People aren't identical and don't react in exactly the same ways, they tend to react along a spectrum. Assuming someone is making a conscious decision to overlook a perceived inconsistency is not a fair assumption, they may just be more naturally tolerant just as some will be less so.
