If Bernie was elected in 2020 nothing would have changed with Israel's genocide. We would likely be in an identical situation in regards to "the empire" as Biden, there was very little foreign policy differences. Maybe he would have dropped the embargo on Cuba (MAYBE) but then Trump would win and do what he did anyway, and the CIA would use it as an excuse to do a bunch of infiltration and get a bunch of assets in the country like Obama.
In retrospect Bernie definitely did NOT have the sauce to push back the blob. You always want sauce against the blob.