Can SvE fix anything with the economy or keep players in tf2? I personally think no just because of the rise in the amout of ref keys are becoming worth. The best valve could do is make ref buyable in the mann co store, but I've been wrong before.
It'd be downright impossible for the update to directly fix the economy, but if the competitive mode Valve is hinting at is actually a thing, it could be a whole new story for TF2 player mass, maybe for the better, if new things come from the update, that could also change the economy indirectly but not by much, this economy is already done with these 6 key buds.
A string of new and temporary craft items would murder keys. When the bread box came out, keys dropped in value by about 3-4 ref if I remember correctly. A string of those would easily knock keys down by 10 ref... Provided there is good stuff in them.
It's definitely a possibility, I don't think Valve would give up on their first game that's also in the top 5 steam games. I'm just hoping that's the case, I don't want TF2 to fall. Will something like the Bread Box come out, not sure, will it change the keys by that much? Not sure. But like what Cobalt said, we'll just have to wait and see.
The TF2 economy is not crashing. It went through a period of inflation, and that's caused other items to be worth less, and some worth more. Valve could return the economy to where it was before, but not sure if it's necessary.