In my opinion, i don't think it's about laziness. I think it's just soul crushing to know that we have to do three hours of extra efforts a day just to speak, a natural fonction that most poeple on earth do instinctively, with zero effort, zero overthinking. In this day and age, humans have busy schedules, and three hours a day is a huge amount of time. Plus, speech exercises don't work for all sttuterers, the results vary, and often aren't satisfying.