> Imo V2G, and V2H is unnecessary and add too much complication

I believe that's more a function of auto makers (and charger cos) not trying to do much about it (and grid cos not caring), than a technical issue. The benefits (especially if V2G) are quite significant.

I doubt any car owner will say no to earning revenue from something that costs them almost nothing. The problem is more of "how do we get there at scale". (Disclaimer, I studied this topic in my thesis.)