devtrackers.gg
If you go back and compare the crafting events to the original ones (April Fools Tiger / Cobra + IS-7), we have actually made quite a few changes and improvements to the crafting events. The main point is, some people prefer the marathon style events and would rather we just make the crafting events marathon 2.0 whilst others actually prefer the crafting events, the freedom to simply play the game however you want and earn something just for playing normally as well as many who like the crafting mechanics.
We have also increased the number of events over a year so that both those that prefer Marathon events can enjoy that, whilst also having the crafting events for those that enjoy that. So one does not "replace" the other or "take up" a spot, they are both independent events with different goals to each other.