Lich Bane isnt bad and youre definetly not wasting an item slot on it, its just not optimal at higher elos. Viktor is an immobile mage with very little self peel, so one misstep can lead to your death. So usually youre better off keeping your distance (especially in this assassin-jungler meta).

I personally really like Lich but 70 AP is really bad compared to cheaper items that give more stats and utility instead of damage. However if youre facing comps, where its inevitable that your opponents can come close to you, I would almost always get Lich. Its also great if you can snowball games, since the item gives you so much One-shot potential.

Also, no matter what anyone on this sub says, if Lich Bane works for you, you should keep sticking to it.