As someone in a poly marriage, kitchen table poly is an absolute requirement for us. If all our partners can't get along together, even if they aren't involved with each other, we don't date.
I have two partners along with my married partner, and they have two partners as well. We get along with all of each others partners, and while our partners don't directly talk, they know about each other and are cool with everyone.
Not a chance if either of us were involved with someone who didn't like the other would either of us stay with them.
Watching tv is beyond her tech savviness? It's actually easier. I just open website, click channel, watch tv.