Median early game gold diff hasn't varied much between seasons in Year 10, but is trending slowly up (Monsters, Hope, Souls):
5 mins - 780g, 815g, 835g
10 mins - 1420g, 1500g, 1470g
98% of Conquest matches at 2300+ MMR have a gold difference below 5k at the 10 min mark. (3/6)