Seriously? Uhhh, because Ost unlocks snares, weapon upgrades, AND grenades in their tech for "free". YOU said Osts teching is more prohibitive, if you want to accurately compare costs, you need to include EQUIVALENT sidetechs. Nobody gets a free repair station, so thats far from equivalent
To unlock the same things, soviets need to spend more fuel. It is 100% false to say Osts teching is more prohibitive. Its flat out wrong.
don't forget all faction get perks and trade offs, brits get heal on the move and in map art flare, usf gets tank crews,wtc