The last time this happened was in 2016-2017, when Dota 2 patch 7.00 was released in December 2016.
Weirdly enough, some of the names that have popped up arent ones that were massively buffed.
The choice of heroes has been made from a combination of high pick rate and high win rate heroes.

But the nerfs were not significant enough to bring him down as compared to others.
Six Ironwood Branches previously gave the main hero 6 damage, whereas they now provide an additional 12.6 damage.
The additional damage on top of two entities hitting creeps makes last hitting a lot easier.

Also, it helps that he can go toe-to-toe quite well against Ember Spirit in the mid lane.
The popular Lone Druid build no longer includes Radianc.
OD is a natural Parasma builder and one of the best carriers of the item in the game.

But he still remains one of the stronger mid heroes of the current Dota 2 meta.
It isnt even like any of his items were buffed.
However, he is a counter to a lot of the best mid heroes in the current meta.
That naturally makes Huskar a popular pick to counter them.