If you are balding (especially in your 20s) your hair loss will continue throughout your life. If you fix the corners of your hairline now, in 10-20 years time, possibly sooner you will just have hair in the corners of your head and be bald behind, a ridiculous look. That is why finasteride is needed. And even with finasteride you will still need a touch up or two in the future.
It's different if you're completely bald, then your look after your transplant will persist but it still won't look that good as the density will be so low, OK for a 70 year old, bad for a 20-50 year old. We only have a limited number of donor hair. That's why hair cloning is the needed.
There's a celebrity here in the UK called Calum Best who hasn't taken finasteride and has had 4 transplants in the last 14 years just to keep up with his hair loss. I think he's almost exhausted his donor supply and he's only 43. The funny thing is that he looked better with his head shaved. Sometimes a head shave is better than a low density transplant with a high hairline, which is quite an aging look.
Can you commit to all of that?