Scamacca looked HYPE in the youth level, as other posters have said, the "Zlatan" was not just height, his very technical style while being a giant made the comparisons make sense. He was the striker I was most excited about it in the youth level.
He started in Serie B at like 18 after some adventures in the NL. Too many moves too soon imo. Probably better for a kid to stay home and play his youth in Roma. Then he got injured and lost a season iirc.
Now he had his full season in Serie B with 12 goals in league and coppa for Ascoli, relegation contender, and just turned 21. Good season, now is his time to consolidate and see if he can become the player people hoped (doubtful) or at least a proper Serie A striker. While his profile is ideal (tall and very technical), Juve is not the place for him and we would find little use. He needs to play and find his football. Sassuolo (they own him) is probably the right place.
Pinamonti is much more ready. Remember that Genoa is terrible and in turmoil. He has like 6 goals this season, and 5 last season with Frosinone. That's 2 full Serie A for a CF born in 99, it's not normal. Of course he isn't scoring at the needed rate for a top striker but as 19 and 20yo he already he showed he can actually play well at the Serie A level. He has the right movements and the right instincts. He is strong, fast, and plays like a proper CF. This is a player I would take as a sub to groom, that can already be useful and shows good projection. It's not an accident that he already goes for like 15 or 20m.
In the youth levels this is the CF class of Cutrone, Pinamonti, Scamacca, Kean. Usually 2 or 3 of them play together. Scamacca-Pinamonti was the pair for the U20 World Cup last year, and they got 3rd place.