I do not claim to be smart but this much I have deduced ...Mathew 24 .3 is rendered in the K James Bible as referring to the "End of the world" and in the NWT as "the conclusion of the system of things"
The Greek word here used is aion meaning (according to Vines paraphrased) a time period of indefinite length, an age , an era. Is that really referring to worlds end? Not specially. Most Bibles today say "end of the age" I leave it to you to decide what age he was talking about.
2 Tim 3 is a passage we used countless times as Witnesses. Frankly, IMHO it just describes the normal condition of mankind . An honest look at social history ought to confirm that conclusion. J W's are guilty of viewing the past with "rose-coloured spectacles" ignoring the bad behaviour and crime that was so common, even before Edwardian days.