Pedantry: what you describe is just "comeuppance". To be schadenfreude, you have to be taking joy in it.
You can have schadenfreude without comeuppance, though that can verge into just plain sadism or gloating. Schadenfreude usually has a connotation that the misfortune is deserved.
So yes, Remain voters (and those who sympathize with them) may definitely be experiencing some schadenfreude watching the Tories hoist by their own petard.
Yeah it wasn’t explicitly stated but I don’t think it’s a stretch to assume the person who used the term in this thread is enjoying it slightly, given the statement that followed it
You can have schadenfreude without comeuppance, though that can verge into just plain sadism or gloating. Schadenfreude usually has a connotation that the misfortune is deserved.
So yes, Remain voters (and those who sympathize with them) may definitely be experiencing some schadenfreude watching the Tories hoist by their own petard.