Why have so many believed every report from Gaza journalists?
In my opinion, reports by Gaza journalists have come under higher than usual scrutiny so the question really should be why have so few believed the reports from Gaza journalists, not so many.
Because Israel has denied entry of independent journalists since the start of the conflict. By independent, I mean a journalist who isn’t born and raised in the current war zone they are reporting from. This is going to create unconscious bias, it’s not a moral failing but a fact. Israel has only allowed carefully orchestrated tours of a few journalists with the IDF which also do not meet the criteria for independent journalism.
Gaza journalists are only tangentially linked to Hamas’ lies and propaganda. Hamas lies and propaganda have been coming from outside Gaza - eg the IRG, Hezbollah, Hamas officials living in countries outside the Palestinian Territories.