It's a hard one. I have a few conflicting feelings about it.
On one hand, if a port can be built to create a new safer route for aid, that could save a lot of lives. If there could then be agreements as part of a peace process for longer term maritime routes in and out of Gaza, that could be useful for rebuilding and creating new options for people living there to seek employment and access the wider world (despite having a coastline, the waters are tightly controlled by the Israeli government and there is no option for people to enter or leave that way or to use more than a very small strip of water for fishing etc) - in the longer term, access to other countries reachable by that route while maintaining a right to go back to Gaza could be a real game-changer for (for example) people in need of healthcare services not available in Gaza.
On the other hand... I understand that plans for ports and accessing oil and other resources in Gaza and via routes through Gaza were previously discussed by the Israeli government and with the US. And 'boots on the ground' can be a slippery slope, as we've seen - I could easily imagine a progression of "our soldiers are safeguarding the construction of this... now our soldiers are safeguarding the installation of this... now they're safeguarding the use of the port... now they're safeguarding the surrounding area too... and now they're safeguarding routes from the border to the port...". Trust in the US government is pretty low, and for good reason when you consider their track record in the Middle East.
So, I don't know. I hope it works. I really hope it does, and that if it has a role in 'the day after', that role is for the benefit of the innocent people rather than a hawkish and expansionist government.