For such a comprehensively specified and expensive piece of kit, to have no Airplay or Bluetooth function built in seems perverse. Puts the M1 way behind the curve.
Given Apple's (deliberate?) poor implementation of Bluetooth adding an AEX or ATV is probably a better option, refurb/reboxed ATVs can be had for £59 if you look around. Both have SPDIF optical out so connect digitally.
Performance wise the Amazon Fire TV is a good option, Android streamer that has Spotify Connect built in. This gives a wired solution with the Spotify app on your iPad working as a remote control.
When I have tried Connect over regular Spotify I always think Connect sounds better, though there is absolutely no reason why this should be the case as the music 'files' will be identical.
Be aware, if you use the EQ in the iOS Spotify app, it is not supported in 'Connect' mode.