[CiNcH]

I can tell you one thing in regards to brand new Android TV devices launching with Google Certified Android Oreo or greater in 2018 / 2019.

They must be Goggle "Treble" (click) compliant, which for Android users means from that point onwards supposedly much faster Android OS updates (click) going forward independant of the hardware the OS is running on. 

AFAIK both, nVIDIA and Amlogic updated drivers and kernel to be Project Treble compliant for their fairly old chipsets (see SHIELD TV and Mi Box). Yet MediaTek is not doing the same thing for their previous generation chipsets. Only latest MT5893 (a.k.a. MT5598) received support. Older chipsets are sitting on a 3.10 kernel which used to be the baseline for Android KitKat...
 

Along with that Goggle has mandated Treble compliant devices must run a modern v4.x Linux Kernel to plug security holes in the older v3.x Kernels. 

Google also mandates a 3.18 for older devices which get updated to Oreo (see here), yet those MediaTek based TVs still use a 3.10 which is even true for 2018 A8F and X90F.


I don't trust Sony/MediaTek for anything. Master Series with MT5893 still has the very same bugs as the old ones. Sure, it is faster now...