Developmental stuttering will occur in any language you speak since it’s neurologically based. It happens in all languages. I’m sorry you didn’t have a good experience in speech therapy. Like other therapies, you need to shop around until you find someone who works for you. You’re right - we can’t cure stuttering and genetics has a huge component in how it develops. But there are lots of other things a competent SLP will work with that will help make communication easier. Stuttering is consistently rated as the area SLPs feel the least comfortable in treating and a lot of therapists use curriculum that just don’t work. They aren’t individualized. Find someone who knows what they are doing!