It isn't season 2 any more.

Irelia got a buff not too long ago. DFG doesn't exist-- the Pentakill band was not told this ahead of time so now the song is sad. Yasuo and Ekko now exist, and strong assassins are getting updated to become stronger again. Marksmen have been updated to be able to either easily reach 80-100% critical strike chance. Juggernauts have been updated to deal late-game Nasus levels of damage throughout the game.

Why say this? Well, the "horror" of Kassadin's 98% pick/ban rate happened back when assassins were bar-none the strongest class. As such, the strongest Assassin was a guaranteed pick/ban.

As each class update happens, we again see this same case of the strongest in that class becoming a very high priority pick/ban until the point where they're nerfed accordingly. Not as high as Kassadin though, because there are now other champions with mobility or other strengths that are a priority regardless of the current meta.

I don't ever see anyone suggesting that he receive his silence back. Anyone who can tell the game state knows that the current meta doesn't give two shits about Kassadin's ultimate. It's the silence that made him so overbearing-- in a meta where the strongest class relied mostly on abilities. As such, even LeBlanc had her silence removed when it was found that she was the next best bet after Kassadin lost his.

But now? Every champion that Kassadin previously hard-countered due to the combo of his silence and mobility has become a hard counter AGAINST him instead-- because their bursts contain hard CC that renders his ultimate useless.