No one can give a $$ to product in exact terms. You are buying in game currency and can spend it for an advantage in many ways.
Some players benefit more from shards, others from gear, and other could find an advantage in farming refreshes, or mods.
Since there is no single path to spend and get an advantage that suits everyone, there is no single answer.
There is also the fact that you dont have to spend at all and can play this game with no issues, and always be able to get everything in game without any $$ spent.
There are many packs put there that are a direct purchase, but those are usually situational and are not going to be a real advantage for everyone.
For these reasons and others, the dev team cannot answer this question for you.
Players may be able to give you some general amounts to do well in X event, but they would need to know where you currently stand. (Players are at all different areas of the game, which is another reason it's hard to quantify an advantage)