I think Mamdani is what I'd call a center-left. He does suggest some moderate forms of wealth redistribution (via higher and more proportional taxes, which can then be used for food, transit, etc) and some very mild redistribution of means of production (city-owned grocery stores etc), all while keeping the wider capitalist framework. While not a radical leftist, I think it is an amazing step forward for the US, and pretty much the best new yorkers can hope for outside of a socialist revolution.