That's fine, IF those things can be rooted and have released any proprietary drivers so you can load your preferred ARM-compatible Linux distro.
If, however, you want to run Plan 9, RISC OS, FreeBSD, Haiku, or anything else that isn't Linux, then you'd probably still come unstuck regardless of Alibaba's openness.
in terms of buying products from alibaba, most equipment on their uses the MTK tool chain. MTK offers full drivers to run most of their hardware, and can run under a multitude of Android OS is. I also have a friend who took the MTK tool chain and installed debian on his HaiPai Noble N7889 phone. It didn't run very well at all, but it did run.
If, however, you want to run Plan 9, RISC OS, FreeBSD, Haiku, or anything else that isn't Linux, then you'd probably still come unstuck regardless of Alibaba's openness.