This thread is dumb, but I'm going to try making a thoughtful reply and see what happens:

This is a bad deal for the short term -- it leaves US allies in a bad spot and will certainly increase the proxy war between the Saudis and Iranians. Israel will be pissed about Iran's threat to their homeland, but honestly Israeli leaders are just grandstanding for the local populace; they're safer with Iran being a friend to the west. When it comes down to it, the powers-that-be in Iran won't attack Israel anyway because they know Iran will be ruined by America if they do. Egypt, Turkey and Israel (and Jordan, UAE, etc) have reason to be really pissed about the security implications in general; the proxy war in the region is going to inflame and lots of US allies may be in the line of fire.

But if this is part of a longer term strategic shift for the US away from the Saudis and toward Iran then I think it's a good deal.

Think about the trajectory of the region: Iran is becoming more moderate, their population wants reforms and internationalization. In another generation (or less) the revolutionists and death to America crowd will be dying off and getting marginalized; without sanctions and never-ending threats of war it's more difficult for hardliners to have a soap box to stand on to rile people up. Contrast that with Saudi Arabia which has far strict controls on freedom that likely won't be improving any time soon.

Iran has some semblance of a democratic system which runs the day-to-day aspects of the country. Saudi Arabia is an absolute monarchy where princes manage day-to-day aspects of the country. If the ayatollah becomes a figure head moreso than someone who actually wields the final say when they want to then their system of governance looks more like a constitutional monarchy than a theocracy.

The Iranian constitution actually reads like a document focused on governance; the Saudi constitution is literally the Quran.

The Iranian economy is more mixed (while still being underpinned by energy) while the Saudi economy is basically JUST oil and not much else. There is so much more investment opportunity for the west in Iran than there is in Saudi Arabia.

IMO Iran is a lot more attractive ally and trading partner than Saudi Arabia for western countries. If deals like this can push Iran from foe to friend then that's probably a good thing for western countries in terms of security and economics.