It's fine if you don't like The Big Lebowski and movies by the Coen Brothers, personal preference and all, but that doesn't take away from the movies being objectively great.
You can say you don't like them, but that's where it ends, because they simply aren't bad movies.
I don't like Breaking Bad, but i won't debate on it being a great show.
It's not so easy, though.
Who says it's great? I'm here talking about any movie, not Lebowski nor any Coen brothers work. I see tons of super hero movies that I find stupid and are rated highly. Also, eventhough it's not a great parameter, but when you look at the imdb top 250 list you have the most rated movies amongst audience (dunno but I don't think there's any bigger site regarding movies and numbers). There are plenty of movies with extremely high rating and number of voters, but does that mean they are objectively good? I wouldn't say so. I happened to watch some that I did not like at all and they are rated really, really high. There are also scenarios where you find movies that aren't rated good but they'd enter your fav list movies, no?
I can understand someone not linking Breaking Bad or Game of Thrones due to the thematic background and simply not being into it. I could even understand that somebody likes GoT for the effects, politics but himself not enjoying such show. That means he doesn't like it. When that guy goes on imdb to rate he surely wouldn't give 10/10 thinking how it's great, but he doesn't rate it high himself.
It's not like I'm anti sci-fi yet I'm preparing to watch a sci-fi movie. Nor I'm anti adventure type of movie yet preparing to watch one. It was Lebowski, quite neutral movie where background topic doesn't bother me at any level. I found it to be a normal movie (I think I rated it 6). I don't see how I can say "it's an amazing movie, but it's not for me". If it was amazing for me I'd nail it as a 10 right away.
There are plenty of movies that are rated highly but I didn't like them personally. Like
Django,
Requiem for a Dream or
Amélie Poulain. However, I'm sure there are tons of people who'd list those movies as their fav movies of all time and for them that's quite often objectively. Again, I just don't see how can I say "it's great movies, but not my thing".