While it hurts me to say, the posts above are right in regards to Ridley suffering against the majority of characters that have the most showings during high level, top 8 tourney play. Ridley does have a solid air game that can shake your opponent up if they aren't ready. I wouldn't consider myself that good with Ridley, but I would say that high level Ridley play relies quite a bit on strong reads and a focus on ledge trumping and ledge guarding in general. Ridley plays well of the stage as long as you are staying close to the edge. Spacing and overall awareness of your opponent, especially if you're playing against sword characters, will save you from getting demolished. I like using my neutral b to catch sword characters off guard and just rush in, faking out during the rush in usually throws the opponent off, leaving them open for attack.
I also see Ridley being able to maintain a strong presence in top level play, expect nearly all matches being grueling and drawn out in length, patience will be your best friend during these situations. I feel like a lot of this applies to maining any character in ultimate but it still applies to this discussion, I think.