Its not just about DHT. You are just genetically programmed to loose your hair, and androgens transcribe this information through the AR.
5ARi's won't do much. It just slows the progression down by reducing the strongest androgen in your body.
I personally would call this like a cup of water with a hole beneath it,... leaking water....
Thats why some got a bigger hole, and some a smaller. Some stop the progression of male pattern baldness for a decade, some for a year.
Or you could simply understand it like... a train, trying to reach its destination, but you just slow the train down from 100km/h to 50km/h... nevertheless, it reaches it's destination lol.
I personally would feel insecure sitting only on finasteride, and yeah,... I am.
I will try to stop the train, or to fill the hole in my cup. So I can finally sleep "well".