Russia is a huge exporter of diesel fuel. Ukraine is blowing up Russian refineries. This probably has just as much if not more of an effect on the overall world supply of diesel.
Add to that refineries closing in California due them not wanting to spend one billion upgrading that refinery.
The USA produces MORE diesel than our domestic market consumes. Those exports primarily come from LA & TX. They do not have as much on the price delivered to the Pacific coast of the USA or New England or even the Upper mid west.
That is because the diesel fuel in those areas typically comes from other refineries.
The diesel issue is a world wide problem. The conflict with Iran is just one factor contributing to the current price increases.
The problem is NIMBY. No one wants a brand new refinery built upwind from their house or their water supply. Just like they don’t want a nuclear power plant upwind from them.
By volume, the Russian refineries’ damage appears to PRESENTLY be about the same (shortfall).
However, Ukraine also hammered over 200 ships in Russia’s “shadow fleet”. That affects both crude and refined products, of course.