As has been said, a Goldberg return would generate a ton of buzz from the start without any real degree of needed build up because nostalgia would do the trick.
Lesnar vs. Goldberg would draw, no question, and I can understand why WWE would go for it as money is always the name of the game; anyone who says otherwise is fooling themselves. I personally couldn't care less about seeing it, however. I didn't give a damn about Goldberg 20 years ago and I don't give a damn about him now. If they did have a bout and Goldberg went over, a man who turns 50 in about 6 months and who hasn't wrestled in over 12 years, I couldn't help but view it as a slap in the face to the rest of the roster.
I honestly think that anyone on the roster that bitches about Goldberg being part of the card need to pipe down and be happy he's there. Like you said, Goldberg wrestling again after 12 years would generate a buzz and likely improve the PPV buys.
If you were a wrestler would you rather be part of a PPV without Goldberg and less PPV buys, or a PPV with Goldberg and more PPV buys?
This isn't about who goes over and who takes whose spot. Assuming all wrestlers benefit from a successful event (and taking into account some benefit more but let's not piss Ryback off), if I were a wrestler and I had a guaranteed spot on that card I'd pray Goldberg gets a spot on it too. More money for me, more eyes on me, more attention for me.
The only case where someone would be rubbed the wrong way would be if I'm a let's say AJ Styles, I'm supposed to go up against Lesnar at Survivor Series, then Goldberg comes back, they take me off the card and replace me with Goldberg. That'd piss me off.
Other than that, I don't see what the big issue is. Just let the motherfucker get on the card, make the event more successful and everyone benefits. He's gone in a month and all those "hungry wrestlers" will get their chances.
Besides, the locker room in 2016 doesn't seem to be as bitchy about who does what as they used to be 15-20 years ago. I really wouldn't worry about it.
I'd watch the match, I've always enjoyed Goldberg, he pretty much has to win unless he's fighting 'Taker or Lesnar and that's it. Beating Goldberg never made anyone's career; not even Kevin Nash's. He ain't Hogan or Rock or Austin or Sting.