I agree that the proxies can become more of a liability if they're weak, but they're also a deterrent against Israel if they're strong. Propping up Assad was a major foreign policy mistake, because it turned out that he was too weak to survive on his own and an Iran aligned Syria was too close and threatening for Israel to accept. But that's in the past anyway. As for the Palestinian groups, there's a lot of fiction in the media. Hamas doesn't get weapons deliveries from Iran. Iran didn't order the operation against Israel in 2023 . They should certainly stop the rhetoric about Palestine that makes people think that Iran is a major supporter of Hamas.
Supporting Hezbollah and Yemen is cheap, makes an Israeli attack more costly and moves the first phase of conflict away from Iranian soil. Will cutting off Hezbollah and the Houthis make Iran safer or less safe? Preemptively disarming the Houthis is not going to help anyone.
Other than the historical support for Syria and the Iraqi and Afghan insurgency, I don't see the proxy groups as a source of conflict between Israel or the West or the Arabs and Iran. Hezbollah and the Houthis are not a source of conflict but increase the little deterrence that Iran has against the west. Would Iran not have been attacked if it hadn't given weapons to the Houthis or Hezbollah?
Publicly criticising Israel and speaking up for the Palestinians is probably a bigger mistake. But ahmadinejad is long gone and the current government is speaking in a very mild tone. That won't stop western media from repeating the "wipe off the map" quote