Apple has confirmed to The Verge that lossless audio is exclusive to Apple Music and thus subscription-only. The company won’t offer music purchases in lossless quality, nor will there be any way to upgrade owned tracks to lossless with the paid iTunes Match service
https://www.theverge.com/2021/5/17/22440090/apple-music-lossless-audio-dolby-atmos-support-audio

やっぱりか・・・