There are many ways to spend an exorbitant sum for a linear power supply, but it's unnecessary. In a recent YouTube video, "Gabster" demonstrates measurements for various linear supplies, with the inexpensive Studer 900 clone performing exceptionally well for the money, demonstrating excellent voltage regulation with an impressive <1μV of ripple.
The "Studer 900" LPS in the link below can supply at least double the current of the OE 5V/2A unit supplied with the WiiM Pro Plus, and is around $100 delivered, USA tariffs included. I have used this with both a WiiM streamer and Geshelli Labs J2S DAC and have been 100% satisfied with the performance as compared to noisy OE wall warts.