I don't think there's anything "usual" about stuttering. Allegedly my grandpa also used to stutter until his early twenties and then he just stopped completely. Being near to 30 by now I'd say that my speech has improved a lot in the past 5-7 years. However, I mostly ascribe it to caring less about what others think and to me having more confidence than as an insecure teenager. I used to have it really bad. When I joined the labour market I also realised that people don't actually care nearly as much as I told myself when I was younger. Most people have something that they're insecure about and focus more on their own struggles than others'. At least that's my experience, luckily. In the beginning, I had a lot of anxiety when I had to be in meetings, Teams calls etc but it's slowly disappeared with time, even if I still don't exactly seek out doing presentations. I also find that it helps that when I have to present myself to a new group of people that I tell them straight up that I have a stutter so they know what's going on. I generally do that after experiencing a block to kind of "break the ice" and make myself less nervous. Another interesting reality is that my wife and I communicate in English (which is not special in itself, but we both have different mother's tongues) and I feel that speaking a different language has got my stutter working differently. I also tend to, say, use an English word in place of a word in my language if I know that would've caused me to block