I think "legalize it" in the platform is more likely to help a democratic presidential candidate than hurt one. Specifically, I think it might attract more liberal voters to the polls in swing states with illegal weed such as GA, NC, and WI.

I agree that I would expect a serious candidate to come with much bolder ideas, but it can fit into a platform in the same way "no tax on tips" fit into the 2024 election. One of many good ideas that will motivate a certain niche of voters.