Finance created lots of value for the British Empire when they were colonizing countries - where they could raise money to buy navy ships and soldiers.
Finance does create value in the long run. However, it creates minimal value in the short run. Debt being traded in the short run is a zero sum game which does not create any value for the society. Considering that we allocate the best and the brightest people in finance, I would consider it creates negative value to society.
It's fiat currency and fractional reserve banking - the initial bootstrapping of the system is a giant 'just trust us' and 'go with it' moment for society. Debt is easiest way to grow an economy, as loaning money helps create new wealth. It allows banks to turn $5 actual dollars into $15 actual dollars, without having to take $10 actual dollars from anybody. It's magic, but it only works when people trust the system to not disappear/default, and borrow money. Without debt, there is no growth of the overall economy, there is only shifting of reserves from point a to point b.
And in any case, I'm not saying that finance is absolutely useless, I'm just saying that the focus on finance (and the return they get) might be too much for our society/ market nowadays. Thinks of it similar to the manager and developer situation, you need product manager to make a bunch of developers to work together, but if you have a 10:1 ratio of managers/developers, then you probably can use a few more developers.