Most people are not realizing this: as demoralizing the performance of Iran might be aerially militarily to the US/Israel/West; as long as the Islamic regime does not get removed, they will still “win” this conflict (and the US/Israel will lose).
The US is desperately looking for “local partners” (Kurds, Baloch, Arabs etc) to remove the regime from power, as it cannot “afford” to put troops on the ground in Iran and get in a protracted war. It will be worse outcome for the US than Afghanistan and Iraq combined. That is why Trump is not supportive of Pahlavi coming into power, as he doesn’t want the US troops (especially ground troops) to do all the work for Iran.
The US is also relying on exploiting internal rifts within the Iranian security establishment (IRGC and Artesh) to remove the Islamic regime, without any success.
There is currently no indication that the regime will fall quickly, and the US/Israel need quick, “clean” (similar to Venezuela) results of removing the regime, but they are not likely to get that.
I believe Trump’s plan, if he is not able to topple the regime in the next few weeks; might be to declare victory claiming the death of Khamenei. That will not be a real victory for the US and Israel though: as long as the Islamic regime stays intact, they can always rebuild their missiles capabilities; and will be a constant threat to Israel. Israel will not be happy until the Islamic regime is toppled and is replaced by a pro-US/Israel regime.