On lap 56 of 66 in a round dominated by Red Bull driver Max Verstappen, Alfa Romeo driver Zhou used DRS to challenge Tsunoda for 9th on the outside entering Turn 1 right hand.
But as the corner transitioned into Turn 2, Chow appeared to shake his machine to the left, before rejoining the track several car lengths behind Kakuda into the escape lane.
The FIA stewards reviewed the incident and ruled that Zhou was ahead at the apex of Turn 1 and therefore had the right to enter the race room.
As Tsunoda was found violating the International Sports Code, he received a 5-second penalty and dropped to 12th without points. Zhou, meanwhile, scored two points for ninth.
Asked by Autosport about his reaction, Tsunoda said: “It’s a ridiculous penalty and it feels really unfair.”
Recalling his take on events, Tsunoda thought Zhou had “pretended” to run out of space and that there was “definitely” room to keep the Alfa Romeo on track.
He said: “I left the room when I saw (Zhou Lai), I think he gave up early on.
“He went outside and pretended he was being forced out, but he didn’t. Sure enough, there was room outside.
“Obviously I put pressure on him, but there was still space, so I don’t understand why it was a penalty. It felt really unfair, really harsh.”
Tsunoda said he was not aware of the penalty until it reached the finish line, and believes drivers and teams should be able to present their defense to the FIA before the final ruling is given.
He said: “After I just heard the checkered flag, I was really happy. But after listening to that radio, I was really disappointed.
“At the same time, (I think) it’s a bit of a curiosity … it’s good to have some discussion with the FIA because they gave five seconds without any discussion and the race was over.
“So, it didn’t feel fair … (I felt) exhausted and flat.”
In contrast, Zhou believes that this is a dunk penalty for Kakuda. He said: “It’s very simple.
“Going into Turn 1 and into the middle, I was in the lead and I actually gave a lot of space. Then I saw that he (and him) didn’t stop.
“(He tried to) release the brakes (but he) drove me away and I had to take avoidance action and (use) the escape route or we would collide.
“So, it was tricky after that because I had a lot of rubbish on my tyres. But in the end, I was able to stay in the right position behind him and regain the position.”