LattePanda Mu is a versatile micro x86 compute module with an Intel N100 CPU, designed for custom designs with support for Windows and Linux, flexible thermal management, and extensive interface options for a wide range of applications. Its CPU performance doubles the Raspberry Pi 5.
But with a price starting from 149$ it also doubles the price of a raspberry. I think if you are looking for a cheaper alternative to a Pi, go for used/refurbished thin clients that ran out of leasing. At least here in Germany they are often sold for cheap.
A better comparison would be the RPi compute module 4 since both need a carrier. A thin client like you mention, or one of the recent sub $100 n100 mini PCs would be a good alternative.
If you're in Germany checkout mydealz.de. There, such offers are posted by users more or less every week. There are similar user-driven deal websites in other countries (HotUKDeals, CholloMetro in Spain, Pepper in Poland, ...) but these I don't follow regularly.