The newer series stuff is all 64bit ARM which is currently problematic for sailfish porting, but work is being done to get that sorted though so it might be worth a risk.
I think the main issue with 32bit mode is that you'll need 32bit drivers to go along with it, which aren't available. So what was tried was using the 64bit android base with a 32bit SFOS on top which booted, but was otherwise reasonably broken.