There have always been problems with "rules lawyers" who don't realize that the rules are there to help the DM make a fun and challenging game.
I think the internet has made this worse. People sit around lovingly crafting weird, morbid stories with an undercurrent of self-loathing about the horrid behavior of other gamers and DMs. From all of this you would get the idea that there are only 2 or 3 actually sane and functional people who game, and they must desperately cling to the Unyielding Laws given to them by WOTC on golden tablets as their only defense against the vomitous hordes of subhumans calling themselves "gamers".
Whereas in my decades of gaming I have only seen a few people who were truly boorish at the game, and that was easily solved by just not gaming with them again. I have never had to desperately cling to written rules as though they were a life preserver.
The DM has the hardest job: he makes the world, he makes the scenario, he makes up everybody in the world/scenario, he sets all of the situations, he is responsible for everything being challenging but allowing for a successful resolution (a finer balance than one might think), and if the whole mess, into which he has invested many thankless hours, doesn't turn out to be fun in play, it is the DM who will be blamed (even if they acted like donkeys the whole time: "But my elf doesn't wanna go to the Pits of Mordecore - they sound scary!"). If the rules were so absolute that even the DM was not allowed to monkey with them, it would be a worthless job indeed. But if the DM employs the rules as his ally, there's actually a chance that he might be able to make the game fun for everyone, and have fun himself in the process.
Then I suppose there are those people who don't have the "gamers are scum, except me" pathology, but who are simply so stuck in Information Age metaphors that they think they think of the rules as "code" and think of the DM as the rectangular box with the big button on the front that they push when they want to make a raid on "Forge of Fury".
DM /= computer.