smartphone can't play it without resampling, and Bluetooth without reencoding

Straight from the article that you could've read:

"For the smoothest and best listening experience, we recommend streaming lossless music on Wi-Fi using wired headphones or speakers on a non-Bluetooth connection, like Spotify Connect. Currently, Bluetooth doesn’t provide enough bandwidth to transmit lossless audio, so the signal has to be compressed before being sent."