Typically an advanced aquarist fish.
Difficult to teach to eat prepared foods.
Will struggle with food inside the tank if others are competing (wrasse) and faster (worms, pods).
Size.
Temperament (calmer fish).
With that out of the way let us talk about today - smaller size - to tomorrow - larger size and what that means. Why? Because you are already in this boat with a yellow tang that you may have to catch and move to another tank (upgrade) or return to the LFS (for a few pennies on the dollar). What does this mean? It means you have to:
A. Ask the fish to pack its bags and walk into the net to be caught
B. Said fish will ignore, rightly so, and now you have to trap and hope it works
C. If trap fails try barbless hook
D. Barbless hook fails and now you have to remove rock, coral, and lower water
A through D stress you the hobbyist and the fish. If you have to result to D then you will have a mini cycle and potential loss of coral(s) because you will not remember the the original placement. See how this is turning into one big mess because it may or may not be easy to remove said fish be it a tang, damsel, six line wrasse, or butterfly?
If this doesn't answer the question let us try this. Pick up your laptop or phone if you are visiting this forum on those devices. If you are using a desktop even better. Pack it up. Stand up, find the closet near you, open the door, step in, turn around, close the door, and reply here. Let me know what you think. Set timer for about on hour and hang out, surf, read, post, go about your business. Once hour is over, open door, find your bedroom, office, den, or great room. Repeat the process. Post again.
How was the experience between the two? Felt different? I bet it did. You and the yellow tang are now one. Onus is on the hobbyist to do research and provide the pet a proper environment. To the best of "our" ability. That may mean we can't keep some fish we want as a side effect rather than asking questions looking for an answer we want to hear. Not saying you are - just noting it.
Oh yes, remember 75 gallons is just the tank estimated water volume. It is actually less once you factor in the substrate and rock. Something to keep in mind which is why I said go to the closet

. I'm sure you have coats, chairs, vacuums, or other crap in there that will limit your space.