Helping out my father in law.

He needs a dual zone system.
2 speakers outside.
4 speakers in living room (but one of the 4 wires has two sets / 4 wires of speaker wire?)

Just wants to be able to play streaming music from an app (native or from his phone) and whatever the TV is playing (Roku soundbar so should have Arc outout?).

Grok recommended a $900 demon x1800h which seems like overkill

I think this would do it:

https://www.accessories4less.com/make-a-store/item/onktxsr494-rb/onkyo-tx-sr494-7.2-ch-x-80-watts-bluetooth-a/v-receiver/1.html

Thanks.
I think the main limitation is the 2nd zone does not appear to independent.

Seems that is only in higher end models.

I think the Denon s970h would work too. You should be able to find one of those two for 600 on sale. The s and x series don't have a ton of differences, I think room correction is better for the x. I have an x1800 and use it for this same purpose and it works well. You can set up the zones in the Heos app and then stream directly to them through Spotify by selecting them as the output speaker