It's not as easy as you think. In EP9, Maya clearly asks the MC if Zoey and the MC never said the words "I love you" to each other. The MC says so that wasn't the problem, but that they never used the words "girlfriend and boyfriend".
As you correctly wrote, the lack of communication between Zoey and the MC is her fault. But they said it to each other so that they would love each other. EPP. This is where many people's thinking lies. The three words “I love you” are just three words, nothing more. These three words mean nothing if you don't show your love. This is the real problem between Zoey and the MC. They couldn't interpret the MC's gestures.
Many forget that not only does Zoey know the MC very well, but the MC also knows Zoey. What doesn't Zoey like and what makes her uncomfortable? When people talk about feelings. The MC knows that, we read that in the game. When you love someone, you will refrain from doing anything that makes your partner feel uncomfortable. This is how you show love and then you can say the 3 words because the 3 words “I love you” then have meaning.
So the reason the MC didn't say what he actually wanted to say to Zoey at the train station in Interlude was because he didn't want to make Zoey feel uncomfortable. The MC shows Zoey that he loves her by hugging Zoey when he says goodbye. Zoey, on the other hand, couldn't classify this hug and subsequently, Zoey made it more than clear to the MC so that she didn't feel the same way about the MC. When you love someone, that's how you stay in touch, you respond to messages, and you clarify when a picture comes up that's ambiguous. Zoey didn't do any of that. The blame clearly lies with Zoey. The MC acted out of love by not talking to Zoey about feelings because he wanted Zoey to feel comfortable. Zoey listened to Bret and followed Emma and Bret's example. Here's the point. When you love someone, you don't listen to such idiotic advice.
Let's move on to EP9 and EP10. In EP9, Zoey said to the MC so she hopes they can press play. So she thinks she wants to revive the relationship as it was before she left for San Diego. The word “play” is the operative word here. Why? In Interlude, Bret said to Zoey that when Emma got back from Las Vegas, it was like pressing play and the song was even better than before. But Emma and Bret made a mistake when they had sex again. Interlude meets EP9 and EP10.
When Zoey is with the MC, when he reads his mother's diary in EP10, Zoey says something to the MC. What? That the MC is a magnet for women. I'm wondering whether the MC is also a boy magnet, considering Chad's reaction in EP1. It is further implied that Zoey was expecting the MC to be with another girl, but she thinks so that she has the chance to fuck the MC again. It's not about a relationship yet, but more towards Emma and Bret. "Play." We get this “play” clue in EP8 from JB. JB thinks the MC is a "player" and Elena doesn't. Back to the topic. The crucial thing happens during the Thanksgiving party.
Zoey and the MC talk and the MC tells Zoey what he actually wanted to say to her when he left at the train station, but because he was considerate of Zoey, he didn't say it, but showed it with the hug. At the end of the conversation, the MC asks Zoey if she would have stayed if he had said that to her at the train station. And another point. Zoey is unsure and doesn't immediately answer what the MC said to her so she doesn't have to answer. What do we learn from DPC. This leaves us silent about a question that answers it. Zoey's silence gave the MC the answer.
Jacob's decision then seals fate.