none of these tactics were obviously against the intention of FDev when they were still in the game
Yes, because FDev could have credibly thought that logging out to the main menu repeatedly would have been engrossing gameplay or could possibly have had any in-game context...
Such mechanisms were widely accepted and abused to the point that anyone not doing so was handicapping their operations, but to imply that FDev had intended them to be used in the manner they were is a huge leap.