This. I went down the alternative route of being self-employed and taking jobs from job boards. This could be largely done via messenger and I avoided talking. However.. it held back by earning potential and progression. It held back my fluency as well... I think I have largely caught up as I eventually found good clients and then moved on. If I could go back and advise myself, I would tell myself to practice on the phone and make those phone calls. I agree that decent employers will meet you in the middle by providing secondary ways to communicate. Worth noting that it is worth practicing with less stressful calls. Phone a shop and ask if something is in stock. Try gaming online with stangers. Cancel or transfer a service over the phone instead of online. I found this stuff helped me a lot and generally improved my confidence on the phone.