The term Botox neck lift isn’t really a real treatment term. Botox by definition is a neurotoxin that relaxes muscles, which can be the cause of wrinkling. Other than a very minor lift of the brows, Botox cannot “lift” anything.
However it can be used to reduce the appearance of wrinkles in the neck and to relax certain bands of muscles in the neck to create a temporarily smoother appearance. FDA had not approved these uses for Botox though and they come with their own set of risks.
Additionally these treatments can be costly and yield varying results which you may or may not be happy with. So “can” there be benefit to using Botox in this manner? Yes for the right person with the right set of parameters.
Is there typically a huge benefit to going this route? No, there are better treatment options than this that will yield much better and more reliable results that you should consider first. Talk with your doctor and schedule a consult to help you decide the right treatment options for you.