For me it was having no other option at work. I have to talk to people for a living and doing what I do involves talking to 30-35 different people a day with varying issues, not including co-workers. For you I would say first see yourself not as an imposter. You're acting like you bullshitted your way up the ladder when I'm betting you worked very hard. Try to see yourself as the hard worker who stutters sometimes, this might be a rougher patch with your anxiety and depression but there are peaks and valleys. I'm in a valley myself and stuttering more than usual and it gets embarrassing but you just gotta say "fuck that sucked" and move on. Focus on the small victories. Today I said the word sesame when ordering a bagel and didn't stutter and it felt good. Small victories will snowball creating a good feeling for that day overall