Busy with life is basically the main reason why he didn't fill-in more as his hair loss progressed. He was fine cutting his hair really short on top. He was also fortunate to have little contrast between his skin and hair color, which allowed him to shave down to a lower guard. However, once he decided he wanted to grow this hair out for more styling options, he decided to do something about it.
Splitting hairs,
That's correct, he was not on Fin in the early years.
Thank you all for your comments.