If you still miss the AirPort Express because you could connect your audio system to Apple devices via digital Toslink connection over WLAN and AirPlay, you will be happy about Belkin’s latest product: the Soundform Connect.
It receives AirPlay 2 signals via WLAN and outputs them via Toslink or 3.5 jack analog. The power supply is commendably provided via a USB-C port. Thus, both the cable and the power adapter can be replaced. The prerequisite for use is an iOS device with 11.4, which is quite an old version.
Users who like to connect their MacBook directly to the stereo system for music playback via fiber optics can also be the target group: because since 2016, there is no digital audio output on MacBook Pros anymore. So either a new system with USB input is necessary or a USB-Toslink converter. This variant with AirPlay 2 enables the same in principle, but still brings flexibility in terms of the installation location through the use of WLAN.