Demand for reed switches has risen largely in the recent past due to new power usage standards. Reed switch technology uses no power in its passive state, making it a suitable magnetic sensing alternative to Hall effect sensors. Especially, uses where low power consumption is key.
Both switch types have their own specific uses depending on the sensing application. Reed switches are diverse in size, sensitivity and hysteresis. All which can be altered for a given application. While Hall sensors can be programmed to overcome weakness, reed switches are more versatile and energy efficient.
Hall effect sensors work well in high-speed RPM switching above 1 kHz. Additionally, Halls reach higher signal repeatability due to a lack of switch hysteresis. That said, Hall switches operate 500 million cycles in their lifetime. Though, reed switches can switch billions of cycles under 5 Volt loads.
Learn more about use cases in this comprehensive article from Standex.