Sure that a number of us have ended up with say an older Xperia XA2 which had licensed Sailfish OS and wonder what to do when selling it on. From a number of potential buyers point of view there is little purpose in trying to find user for un-licensed Sailfish OS, and so instead make a virtue of its unlocked bootloader as it may realise more on Ebay promoted as a "de-googled device". Although basically Lineage OS underneath Iodé OS (now Android 11) has a slightly different UI and can be applied to XA2 and Tama devices such as XZ2 & XZ3 running "rinigus" port. For XA2 Ultra (discovery) and XA2 Plus (voyager) probably still need Lineage OS as option.