Well, I know a couple of us here in the forum were at one time trying to work out a deal with the devil to be able to have that "pleasing vocal tonal quality", but the terms were unaccectable.

My conclusion, it is a function of the anatomy you were born with, the vocal chords and how they have been used and abused over the years. You can take vocal lessons and learn how to breath properly (and you should do this) but your vocal tone is what it is. Those upper register notes need a smooth elongated vocal chord and a large nasal and oral cavity. If you don't got it, well not much to be done.
Now the good news. None of that needs to stop you from singing as long as you can sing in pitch.

BIAB – 2025, Reaper (current), i7-12700F Processor, 32GB DDR4-3200MHz RAM, 1TB WD Black NVMe SSD, 2TB WDC Blue SSD, 1TB WD Blue, 2 TB SK NVMe, 6 TB External, Motu Audio Express 6x6