The war itself is unpopular, but the long-standing policies that contributed to it, like supporting settlers, second-class citizenship, restrictions on movement, etc. are all generally popular last I checked.
You can't get a man to understand something when his... salary, home, neighborhood, citizenship, country, and government depends on it.
I think people are capable of nuance. Even if one might support settlers or even things like a normal war, that's dramatically different than supporting behavior that in one instance seems to be trending towards literally genocidal in nature (and not the hyperbolic genocide that propaganda always claims the 'other side' is engaging in any relatively normal war), and in another instance is just seemingly psychotic and, at best, demonstrating a severe lack of intelligence - both state and personal.
It's going to be impossible to get reliable polling on Iran right now because Israel's going extremely authoritarian with domestic 'information warfare.' But it's fairly certain that most Israelis will oppose what's happening, once they can speak again. For instance in early 2024 Israeli decided to destroy the Iranian embassy in Syria, killing multiple generals amongst others. This led to a largely performative counter-strike by Iran. And here 74% of Israelis opposed continued escalation if it harmed security alliances. [2]
And the Israeli government decided to carry out the recent invasion when global support for Israel is already at record lows, which means it is obviously going to hurt security alliances, especially in the mid-term (double entendre intended). Search my post history and you'll find I've been notably favorable towards most Trump policies. If an election was held tomorrow I'd happily vote against him (and anybody else who supports this stupidity), a million times over, if he drags us into another forever war. And I think that corresponds to a sizable chunk of his support. People think "we" wanted out of Ukraine out of preference to Russia. In reality "we" just want the US to stop getting involved, and wasting money (to say nothing of lives), in stupid wars all around the world, period.
[1] - https://www.timesofisrael.com/69-of-israelis-54-of-coalition...
[2] - https://www.timesofisrael.com/poll-74-of-israelis-oppose-cou...