>It's because macOS implements kinetic scrolling in the toolkit
Which is the proper way to do it.
Other vendors wanted to emulate macOS’s inertial scrolling but they had to stay compatible with all sorts of legacy APIs that only knew mouse events, so some of them cut corners and started sending these fake mouse events from the driver, to be the first on the market with “macOS-like scrolling”™.
Of course this is very much a bolted-on solution, which leads to all sorts of nuisances like what’s described in the parent comment, and contributes to the general sad state of trackpad behaviour on Windows and Linux.
They’ve pretty much cornered themselves, because fixing it would require a coordinated effort from the hardware/driver vendors, the OS vendors and the UI toolkit vendors. It’s just unlikely to happen unless you own the whole stack like Apple does.