Okay I’m a speech therapist. Firstly, a tongue tie most likely won’t impact speech sounds unless the tongue tie is severe enough to impact feeding. The range of motion required for accurate speech sound production is shockingly low. Secondly, stuttering isn’t caused by reduced range of motion or structural flaws. There’s a neurological basis behind the disfluencies that leads to repetitions/prolongations/blocks and possible increased pressure/tension in the articulators. Stuttering and articulation errors due to tongue ties have two totally different causes and speech characteristics. To sum it up, if you have a VERY severe tongue tie that impacted your feeding as a kid, getting it cut might help you make a better th or r (or whatever). It will not impact your stutter because your stutter is not due to the tongue tie