Vlahovic' main highlight was the 38 goals he scored across two seasons at Fiorentina. But, as was noted at the time, there were massive red flags when it came to taking that goalscoring at face value.
First, because 11 (29%) of those goals were penalties. And second, the remaining 27 were scored from an xG of 22.8, so it seemed he was running hot. The overperformance was particularly obvious in that second season: 0.82 goals from 0.65 xG, 0.58 non penalty from 0.43 xG.
He's since scored less at Juve but his underlying threat in open play has remained pretty consistent across his time in Serie A when taking minutes into account. And it's simply far less than Osimhen.
Vlahovic: 0.43, 0.43, 0.48, 0.37
Osimhen: 0.61, 0.62, 0.65