The issue isn't that Iran is doing bad things directly, it's their proxies forces. You can Google and find a source you may trust more, but here's two[0][1]. Iran was taking much of the money the US was paying them to not build nukes, and funneling it into proxy forces to further their interests in the region. You can dig deeper to understand what those proxies have been doing in the region.
Doesn’t the US use it’s money and influence to further its interests? many heinous and hurtful outcomes are facilitated by such funding around the world. That would include overturning a democracy in Iran and putting it on a course for the governance it has today.
So we should just be OK with that when Iran is the one doing it? You can object to US foreign policy and also be opposed to Iran's attempts to destabilize an entire region causing immense suffering in the process
US had three motives for entering the Middle East. The first was originally the attack on 9/11, the second being trying to maintain one friendly government (Israel), and third was access to oil.
The problem with the first is that the US never came up with a good exit strategy, so we are just kind of lingering over there now. It's not even clear what our objective was from the start (it's all sorta all over the place). There has been an appetite to get the US out, but when Obama got us out, ISIS took charge in the region and Obama had to send troops back in.
Supporting Israel can be done through money and arm sales, so you don't really need forces over there.
Oil has become less of an issue since the US went through. Its fracking boom and generated an oil surplus.
It's definitely a careful balance, while many people don't want to be there, if the US does not have troops there, it could become a breeding ground for anti-American organizations that then want to attack the US. It's a hard problem.
Iran has a shit regime (corollary: all countries' regimes are shit, just some more than others).
To your question, it's a matter of emphasis. You have a fundamentally greater moral imperative to criticize your own government (I assume you're not Iranian living in Iran) and its dealings/shortcomings simply because you can, in principle, actually have some relatively significant impact on its actions. So no, there is no need to ignore the conduct of the Iranian government, but if you place emphasis on it disproportional to what you actually have influence over, your moral priorities are fundamentally misplaced.
I’m not sure I would characterize Iran’s efforts as destabilizing the region, certainly not more than the US injecting billions of dollars of arms into the region.
Really we’re in the endgame of fossil fuels, and arguably control of access to those resources that was the main reason that the US was so heavily involved in that region for decades. But with the green revolution needed and pragmatically quite close in reach, the US needs to fundamentally rethink its involvement.