With the exception of Norwood 0 which is a femine hairline more hairloss never looks better than less. You are really diluding yourself if you think otherwise. George Clooney, Brad Pitt, and Jensen anckles are examples of older men who still look good and youthful because they still have Norwood 1’s.
The phrase “mature or age appropriate hairline” is really being pushed online a lot by hair transplant doctors as an excuse to offer sub-par results and not transplant temple areas - which are difficult to do because of the different angles of hairs. What sounds better “we will transplant you to slight baldness” or “we will give you a mature hairline.” I actually think this is where the idea of a mature hairline looking better comes from.
FYI male patern baldness can slow down anytime based on dht sensitivity of hairs. Getting a “mature hairline” is caused by the same mechanism as regular old male pattern baldness - DHT sensitivity, and is a good indicator that you are not immune to the baldness gene.
Never heard of someone getting a “mature hairline” at 17 then holding onto it past 40.
Good example:
That guy looks 3x better as a Norwood 1 than a Norwood 2