I recently asked LG support to look into this for me, and though I don't have my hopes up for full 4.x on the 2016 and 2017 sets (be it a matter of performance, developer time, or lack of customer complaints), it would *really* be nice to at least get a teaser or two (like Assistant and Alexa support) backported to 3.3 and 3.5.
LG could certainly earn some valuable loyalty points by falling in with the cool kids- the ones who roll out major system updates for years ;)