Hamas doesn't have to win, they just have to make sure not to lose, that is their end game condition for declaring victory.
Israel has trapped itself with its stated and impossible goal of completely annihilating Hamas as both a political and military force. Most serious neutral observers have said that Israel's publically stated goals are unrealistic and impossible to achieve. Scholars such as Norman Finklestein, Noam Chomsky, John Mearsheimer have all suggested that Israel's actions are leading to an unachievable victory for Israel, and heading towards a long perpetual war that only a US political intervention can stop.
We're already seeing Biden forcing Israel and the IDF of scaling back some of their large scale operations and air campaign simply because they achieved nothing tactically, while trapping their forces in North Gaza fighting Hamas fighters who know the terrain better and have laid out traps for the better part of the last decade.
Another thing to note is that Israel is hiding its casualties. If not deaths (which I believe it is), then they're obviously hiding injuries suffered by the IDF, this lie was caught by Israeli newspaper Hareetz who investigated Israeli casualty claims and found that they do not match hospital records which far exceed the official IDF numbers.
Israel was fucked as soon as Natenyahu decided to go for a full invasion, and I suspect Natenyahu did it on purpose. The Oct 7th attack guaranteed his government was going to fall, a perpetual never ending war gives him a chance to keep power. The longer the war goes on, the more people will forget he's the reason for this entire situation, and that seems to be exactly what he's betting on.
We don't need ragtag individuals flocking there on foot.
We need Muslim leaders to form a united front. That has not happened, that will not happen any time soon.
These fantasies may be harmless for those of us sitting comfortably far away but the locals pay in blood.
Doesn't have to be a military response, just a united political one. Together the Muslim world has the power to force European and Western powers to stop their unconditional support for Israel.
But like you suggested, even that's unrealistic. Muslims are too divided. Pakistanis are obsessed with a united Ummah, but the chances of that currently are slim to none.