theory/question on why games are decided sooner

I started playing around the start of s5, and I keep seeing posts about how games are decided by the 10 min mark in high Elo, while in low Elo unless extremely behind there is always a chance the other team will throw it, I am curious if anyone thinks the reason the games are being "decided" sooner is because of either A) that's what the game has become through changes (buffs to champs/items). Or B) the player base as a whole has become far more skilled than they were in the early days of league. I haven't been around long enough to say yes or no. But I have a hard time believeing that someone who is diamond in s7 is equal to someone of equavlent Elo in s1-s3 ish. What I'm trying to say is I am curious if players simply understand how to capitalize on mistakes more easily than in the past, where the overall games skill level might have been worst.

I watch basketball frequently, so a comparison, that makes sense to me would be to compare NBA stars from the past with ones of today, for example People like to jerk off to how amazing Larry bird was (which in his era (s2-3 maybe?) he was pretty damn good), but if he were to play against say lebron/Kobe/Durant (s7 player of the same Elo (all regarded as superstars or high Elo)) it would not be a match by comparison they would not even be in the same category.

Anyhow give me your opinions you hoes!