>The futures market exists for producers and industrial consumers to buy and sell.
The futures markets exist to make it possible to sell product not yet delivered, or in some cases, not even made - speculators are an important part of that.
For every one that makes money there is one who loses and that is part of the process that keeps a commodity market liquid.
Take parts away and prices will rise over a long term.
None of your assertions are axiomatic. Why is it necessary for a (”long”, let’s say) speculator to lay claim to some number of tankers of crude oil instead of an airline? Who benefits from that point if the price rises? Who benefits from that point if the price falls?