I think there's some truth in this, though an issue with any technology is not just about whether it fulfils the functions promised but the setting it works in. People need to consider if their WiFi routers or if their set up is up to scratch for instance.
Every link in the chain adds potential failure points.
I use and have deeply tested and got the 15 minutes drops in Wifi (A&K Connect and Qobuz Service):
=> at home with my NETGEAR ORBI Wifi 6 Mesh (2 satellites) connected to a fiber of 1000Mpbs download and 400mbps upload perfecly operational for 4K TV and Xbox Live gaming in Hi Resolution.
=> at office with an Asus RT AC87 connected to a pro local loop at 100Mbps symmetrical
=> in trains or stations with my smartphones in 4G wifi shared connection (tested with Iphone 12 pro max and Galaxy Z Fold 2)
All these connections limited to an already poor 2.4G and not 5G with the A&K Kann Alpha, get every 15 minutes drops whatever you select in sleep mode in the A&K menu.