I look forward to this manga the most every week. It is very fun to read, the story is great, the art is great, the main characters behave understandably, the humor isn't stale or over the top, and the manga gives insight into the entertainment/idol industry... The series is able to succeed in multiple genres, and instead of getting bored the more I reread it, I get more excited.
It is simply refreshing to consume high quality media that keeps itself fresh. Similar to how technology improves and olympic records continue to be broken, what I have learned from reading Oshi No Ko is that creating manga is an art that continues to evolve. Naturally, I had to read everything else under the author and I was glad to see that his ability to create characters that feel so real can be found there too.
I recently heard from a podcast lately about the concept that sometimes in life you can see a "Live story": it's kind of like when you can see somebody developing and changing directly in front of you, rather than watching some sort of karate kid training montage in the middle of a movie. You might be thinking that Oshi No Ko is also media, and not a person right in front of you, but you won't be thinking that when you read the story.