This is my experience as well. 20's the stutter was there, but not a huge issue. I was happy. Now in my mid 30's, moved cities, have what I would call my dream job - and its way worse. The stress of having a job you actually care about, working from home, adult stuff, the anxiety of living through a pandemic, etc. Hard to pinpoint but it's been a rough last couple years and breaking out of bad speaking habits seems way harder.