A necessary condition for Marshall Plan and Japan reconstruction included occupation by Allies, complete elimination of their pre-war governments, rewriting of their constitutions, and total disarmament: reconstruction on total Allied terms. And Marshall Plan/reconstruction in this was was more than direct USG funds, it signaled an environment that could receive private investment and activity both foreign and domestic.
That’s why a post-Gaza that doesn’t combine some form of Palestinian entity with the total exclusion of Hamas isn’t a slogan but a necessity. Things can’t be done long-term via complex international org and NGOs; those are a bandaid. There’s no states outside of the ME or multinational firms that will be interested in investment in a political entity where Hamas plays a role in post-war governance. For that matter, any local capital will continue to flee and seek safer harbor. Until that nut is cracked you’re going to be hard-pressed to envision a meaningful reconstruction scheme. It also doesn’t help that most of Europe is rightfully going to be more focused on the massive costs ans opportunities to eventually reconstruct and reintegrate Ukraine.