This is just going to be a big wall of text. Go to the end for TLDR.

The most important aspect of a romance story, regardless of medium, is for the audience to feel what the characters are feeling. Sing Yesterday to Me has done the best I've seen in showing me the characters feel by just looking at their demeanor and how they move. The inconfidence, hesitation, fear of change yet fear of not changing, the strength to wish the one you love their best even if the one they chose isn't you can be seen in the way how someone scratches their head, how they clean their house, and how they hold a bag. This is a very mundane show—most of the screen time is spent walking home or eating dinner—but that tranquility allows more subtle emotions to emerge.

The characters themselves are very divisive. Out of the four main cast, you might find up to three of them unlikable. They are indecisive, don't know what they want, take the accompany of others for granted, and hold others back in a way that can seem very selfish. The thing that keeps the show going is the fact that none of them are bad people despite being bad at relationships. All the characters realize at some point that what they are doing is not good for the people they love and the people that love them, and yet they couldn't stop themselves for very human reasons. One character is afraid that changing the status quo will ruin the relationships that they already have. Another feels that the one they love don't look at them for who they really are. Another don't know how to handle the feelings of people who are kind to them. And the last one can't convince themself to quit even when things look clearly not going to work out. The beauty of this show lies in its exploration of the struggle of well-meaning people dealing with their emotions and relations, and the enjoyment for this show hinges on one's ability to appreciate its portrayals of the characters even if you find the consequence of their actions detestable.

As a manga series that started in the late 90s about the lives of people in the early 90s, everything in the show feels vintage. There are multiple major plot points that only makes sense because cellphones and the internet did not exist. The show leans into this, with hand-drawn lines and physically painted colors. The art style balances looking real yet a bit blurry, so that it feels intimate yet nostalgic. Compared to Megalo Box from 2018, which was trying to get the same kind of '90s television feel by intentionally not mastering the visuals at high definition, I appreciate the effort the staff put in to do this right. The art style that constantly reminds a viewer of how old the series is serves as a metaphorical backdrop to characters struggling to move on from their past.

The elephant in the room when discussing this series is the scope of the adaptation. The length of the source material is such that it takes about 18 episodes to tell the story in a perfect world. However, the production did not have the power to fight against the Japanese TV broadcasting schedule that demand shows to fit in 13-ish episode slots. Different adaptations deal with this challenge by choosing a different trade-off. For example, Bunny Girl Senpai felt like every episode was five minutes too short for the dialogues to flow right while Log Horizon season 2 condensed an entire volume of novel into a single episode so that it can end on a climatic arc. With a team of staff that is obviously passionate about the original work, perhaps Yesterday is too faithful to the manga for its own good. As push comes to shove, what fell out was 11 and a half beautifully adapted episodes (albeit supposedly with couple plot lines cut out to reach a reasonable transition point) that jumps across 6 episodes worth of buildup to end at the same place as the manga. Knowing that it would have zero changes for a continuation since the manga has long ended and the show itself is somewhat niche, not reaching the end of the manga would hurt for the staff working on this passion project, but I think that the show, standing by itself, would have been better served if they cut a bit less aggressively and wrapped up open-ended after the transition point.

Sing Yesterday to Me is an anime with strong selling points and big caveats. For those who can enjoy a journey despite a rough ending, this is a subtle, intricate, and well executed romantic drama.