There are 4koma that are comedies but know when its fine to be serious or have permenant real romantic developments and they are a lot less shallow for it- like dragon maid or choir. You will become a LOT more invested and attached to characters that way.
Hear, hear. I actually find that serious 4-komas about horror/tragedy/drama, when well done, can actually be more effective than a longer format, because they cut down on flab and melodrama and condense storytelling into a format of absolute brevity. If the author's competent enough to distil a plot structure or development into just four snapshots and execute it meaningfully, the impact is incredibly high, while still leaving space for subtlety. The best part is that the next 4-koma segment still gives you the freedom to change tracks and implement a new formation. Like most people, I had a low opinion of 4-komas when I started reading manga, but my respect for them has greatly increased in recent times as I've come to appreciate brevity in storytelling. The recent chapters of Machikado Mazoku in particular are great examples of just how far you can go and experiment with the format.
With all that being said, I think the original post was less about 4-komas in general and more about how this series in particular handles things. While it's not bad by any means, I do think the format hurts it a bit- a lot of times, I wanted more development on a plot beat, only to find the tension being dispersed by a joke or a shift to new gag. When I compare it to other age gap works like Haru to Midori, it definitely feels somewhat lacking and disconnected. There's very little thematic integration, per se. Oftentimes, it feels like it was planned as a standard, free-flowing manga and simply written into 4-koma format to comply with publication standards, so the medium never ends up being used to its full capacity. This is just my take on it, though.