A home freezer is the obvious place to put leftover sweets, and it works far better for some categories than others. The determining factor is where the water in the sweet sits.
Ice crystals damage structures that hold free water
Water expands as it freezes and forms crystals that push apart whatever surrounds them, rupturing cell walls and protein networks.
A sweet whose texture depends on a hydrated protein web, such as one made from drained curd, loses that structure and thaws grainy and weeping.
A sweet whose texture depends on fat and crystallized sugar has little free water to freeze, so the same treatment does far less harm.
Dough and nut-based sweets survive well
Fried dough sweets, dense nut mixtures and rolled flour sweets all freeze and thaw close to their original condition.
Reheating fried items in an oven drives off surface moisture and restores much of the crispness that thawing softened.
These are also the sweets most often made in large festival batches, which makes the freezer genuinely useful rather than merely a place to postpone waste.
Freezing speed changes the damage
Slow freezing gives crystals time to grow large, and large crystals do more structural damage than many small ones.
A home freezer freezes slowly compared with commercial equipment, which is why home-frozen sweets suffer more than the frozen products sold in stores.
Freezing in a single layer on a tray before packing helps, since thin items freeze faster than a solid block of stacked pieces.
Packaging determines whether flavor survives
Ghee and nut oils pick up other odors readily, and a sweet stored uncovered in a freezer will taste of whatever else is in there within weeks.
Double wrapping, with the air pressed out, also limits the surface drying that shows as pale patches and a leathery exterior.
Syrup-based sweets should be frozen in their syrup, which insulates them from both problems and thaws back into the right texture.
Thawing is where most quality is lost
Thawing slowly under refrigeration lets moisture reabsorb into the structure instead of running out of it, which preserves considerably more of the texture.
Thawing at room temperature also returns dairy to the temperature range where microbes multiply, and published food safety guidance covers how thawing should be handled.
Freshly made dairy sweets are simply better eaten within their short window, and freezing them is usually a way of keeping something that has already lost what made it good.