Robinson's men battled their way to a 0-0 draw in front of 52,221 at St James' Park to take the Magpies back to the Kassam Stadium, although he admitted afterwards he would rather the tie had been settled on the day.
Asked if he agreed with Manchester City boss Pep Guardiola's suggestion that replays should be ditched, he said: "Are you asking my chairman or me? My chairman wants it, trust me.
"I don't think that would be a bad thing. We're now going to play nine games in the month of February with a squad of 20 players. That's what we have.
"We don't have the funds or the resources to do that, so I think it would be better for everybody if it was finished today.
"It gives us an outcome immediately, it doesn't allow a backlog of games in February and then possibly even going into March, which will have a big influence on all of our players.
"At our level, we play a stupid amount of games – we're going to hit over 60 games this year, which is ludicrous. My players' bodies are at breaking point and I don't think it's fair."
Newcastle, who have not made it to the fifth round since 2006, passed up the opportunity to do so with a pallid display despite fielding an £81million strikeforce of Joelinton, Miguel Almiron and Allan Saint-Maximin.
Indeed, they needed goalkeeper Karl Darlow to deny Marcus Browne one on-one with 20 minutes remaining and then substitute Nathan Holland at the end as the visitors threatened to spring a shock.
Robinson said: "That will be probably the last thought in my mind tonight when I go to sleep: 'What if? What if Browney could have taken that chance?'."
For opposite number Steve Bruce, whose players will now lose much of what was supposed to be their winter break to prepare for the replay, there was intense frustration.
He said: "Frustrated, disappointed, upset. From the first minute to the last, we were never good enough in possession, the way we gave the ball away.
"Our whole demeanour wasn't right and when that happens and you get off to an awful start, it encourages Oxford who, let's be be fair, took part in the cup tie and made it difficult for us.
"But we made it really difficult for ourselves the way we surrendered possession, turned the ball over, and the amount of mistakes we made was ridiculous.
"We're still in the hat, that's what we have got to look forward to, but we'll be better when we go to Oxford a week on Tuesday or whenever it is because basically I don't think we could be as poor as we were today."