Sinner isn't a teenager anymore - he turned 20 in August.
The only other recent player to have similar success is Zverev. Sascha was ranked #18 on his 20th birthday and, within about half a year, rose all the way to #3. He had won two titles before his 20th, both ATP 250s, but then won four more before his 21st, including two Masters. Sinner had 4 titles on his 20th birthday, and has won two more since, and is also now #9 in the world (or will be, tomorrow).
The point being their rises are similar, with Sinner slightly ahead at their respective ages (Tsitsipas was close, but a bit behind, age-wise). And they also line up well with Novak's rise in the rankings at a similar age, although Zverev dropped off slightly and fell to #7 for awhile, while once Novak entered the top 5, he never fell below #4 for a decade.
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Hopefully that isn't too convoluted. The bottom line is that Nadal was a bit ahead, Tsitsipas a bit behind, and Novak, Zverev, and Sinner rose very similarly from around age 17 to 20.