Why is Reply 1988 so high rated, what makes it so good? I haven't seen it

Yeah, it's worth watching. It's probably the best drama to watch with family :)
It's absolutely AMAZING! It's just one of those dramas that has you laughing and crying every episode and keeps you wanting more. Even though I wasn't raised in the 80s, I honestly felt a sense of nostalgia watching their lifestyle and how close they were with one another in that decade without the internet and modern technology. I also recommend due to the actors. They were so perfect especially Ryu Joon Yeol and Park Bo Gum; they made me feel so conflicted about who the lead should end up with (I still shipped her with one more than the other though and fortunately my ship won! Still even if the other character ended up with her, I would still love this drama all the same.) This is one of my favorite dramas of all times and its most definitely worth watching!  
Yes, It's wonderful. Frankly, the entire Reply series is really good. 
one of the best reply series , you have to watch 
i really loved it the beginning but i was hoping for her husband to be someone else so i got my hopes up lmaoooo but yeah it's really good. so well done. i cried so often watching it. i guess it depends on who u ship if u like it or not. u could always just watch the first ep and if it doesn't make i wanna watch more then u kno it's not worth it i guess! 
Yes it is great and nostalgic. Give it a try :)
Its good so far, a nice relax youth family drama, I watch one episode each day since one episode feels enough for one day,  its like watching 20 films
Depends what you are looking for to be honest. I'm not that much interested in family drama.
i'm just as hesitated as you are, but i'm watching it right now bcs many friends in MDL recommended it. I'm in episode 6 now, and it's great!!
If you love slice of life..you'll absolutely love this one.
I hesitated a lot before watch this. You wont regret. It is a drama about everything, family, love, friends, relationships in general. I liked it very much. Everytime I was watching I was thinking "why I didnt watch this before". I think it also gives you the thinking that time never comes back and life is all about choices. I wouldn't say family drama, I would say is a drama about life.
The episodes are pretty long, I think 1 hour and a half, so I think it is best to watch slowly.
I was really unsure of the Reply series. I started with 1988 and was hooked. Some episodes were a bit long and that is why I hesitated but I really enjoy the series. It makes you laugh and cry. It is about friendship, family, and romance. It is also a window into a period of time in history and culture. In Reply 1997, the nostalgia of obsessing over a boy band is all too real.(I'm thinking of you New Kids on the Block) In 1988 it is interesting to see the excitement of a country hosting the Olympics. But what makes the series, is the characters. Give this series a chance. 
I dont like family drama before but reply 1988 is a good one. Just try to watch it hahha. 
Coz it's one of the best kdramas. I really liked it coz it made me laugh (and cry).
i liked it but i was born in the 80s, not sure if that made a diff or not.  it felt like id lost an old friend when it finished, i cried like a baby haha