Genuine question: what is the expectation from "world speaking out"? Say the whole world says "don't do it". Do we think they'll be like: sure, since you insisted.
Or to put it differently, when did no-action condemnation help anyone?
The Iranian regime's mass shooting of unarmed protestors is horrifying & a gross violation of human rights. They are striking teenagers & ordinary families. They also have shut down communication platforms. The world needs to speak out against this barbarity and call for it to stop. The Iranian people are justifiably angry about the repression they face, and they know that the country's wealth has been wasted on supporting terrorism and war in the Middle East.
The United States though should not engage in military intervention or strikes without Congressional debate and authorization which will only be used by the Iranian regime to stoke an ugly nationalism.