For me having multiple endings prevents using V ever again. Unless they are going to basically say...we don't care what you chose, this is what happened according to us
Not entirely true.
They can do the "It's an indeterminate amount of time later and everything managed to defy the odds and get back to normal using undefined means and people only vaguely recall what happened" thing.
Whereby irregardless of the ending people chose V still manages to be a protagonist again.
Of course, such a thing still devalues people's choice of ending by making it not matter (Similar to creating a canon ending). Which makes it a not particularly ideal scenario, but it's still possible.
Why so? The fate of V is pretty much the same in every ending. The fate of Night City is far more problematic to manage, IMO. If they can deal with it, they can deal with V.
Actually quite the opposite. Night City is easier to manage than V. Given that Night City basically doesn't change given the ending. Arasaka takes a hit (But is still a giant mega corporation that will continue to do corpo things and will have the resources to re-establish themselves in NC again just like how JS nuking the tower did nothing) and that's the only major thing to happen to NC with exception of a few characters like Adam Smasher, Yorinobu, Panam, Songbird etc being affected by some decisions
V has things occur such as the inability to ever use cyberware again, complete deletion of their mind (Having their body completely taken over by JS), dying completely... Or just simply leaving NC.
Simply setting Orion somepoint in the future, far enough where characters like Panam, Songbird etc won't be around is enough to completely negate any effect on the actual city that any choice will have.
In order to have V return, Orion would need to directly reference an ending in some way. If only to create some explaination as to how V manages to continue to exist as a Merc post Tower/Temperance/V's death endings.
In addition to this, with V's return, it means Orion is still set within V's lifespan (Outside of some BS like "V's engram was uploaded into a new body like 100 years in the future") meaning that not only will endings need to be resolved for references, but also other decisions that people have made throughout the game. Things like where did people send Jackie's body? What happened with the Voodoo Boys? What happened with Takemura? etc. Things that are likely to be referenced if we continue the story of V.
While it's possible to translate all decisions into Orion (We've seen such methods like save file transfers like in Mass Effect), it does mean needing to do more work, as you'd need to create content around each possible decision.
Meanwhile, simply setting the game far enough away from the events of 2077 that such decisions aren't relevant and you don't have to worry about that. You only have to make content based on the decisions made in Orion itself, drastically reducing workload.