Sesame seeds change both flavor and texture
The idea
Sesame can appear as a paste, an oil-containing seed or a topping with a small crunch. Those forms create different experiences even though they come from the same ingredient. A dish with sesame sprinkled on top is not necessarily similar in texture to one blended with tahini.
A practical next step
Ask about sesame in the whole dish, including sauces and garnish, when planning for someone who needs to avoid it.