Get a dropdown for Views: Filter: Taxonomy Term Name
If your views is based in content type, you should use the term reference field in the filter. Example:

I have a content type of services composed of title, body, service category(term reference).
In my services views, I will add service category as filter. In my Better Exposed Filter, I can configure that service category if I want a drop down filter or autocomplete.

Using taxonomy term name shows autocomplete filter.

I hope it helps