5E Readying costs you a reaction, which was not the case in 3E, but it doesn't cause a permanent initiative hit. As long as you're confident of not having your concentration disrupted, you can take advantage of this to double-tap a foe; for example, Otto's irresistible dance to impose disadvantage on Dex saves, followed by disintegrate before the target has a chance to break the effect.
As in every edition, mastery of the initiative rules is a powerful thing.![]()
Not to be a buzzkill but Ready is an action. The wizard cannot Cast a Spell and also take the Ready action in the same turn.