Ronaldo's position at Juventus was only as a complement, when Ronaldo came, Juventus was at the peak of its glory. Ronaldo came to Juventus at the right time, even without Ronaldo Juventus had won the Italian League in a row. Now just look at Manchester United's performance, if Juventus' success is considered the Ronaldo effect, why at Manchester United Ronaldo cannot improve Manchester United's performance.
No, when at Juventus ronaldo became Juventus' goal machine. If I'm not mistaken he made 101 goals during his 134 games with Juventus. So at that time Juve became in need of Ronaldo, when Roaldo Was absent Juve often had difficulty scoring goals. The problem continued when ronaldo left, Dybala could not perform consistently, Morata was the same. They kind of lost confidence making it difficult to score. In fact they were hard to win in the early match after ronaldo left.
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https://id.wikipedia.org/wiki/Cristiano_RonaldoRonaldo's departure at that time was indeed one of the factors that made Juventus slump in this regard. and indeed it was proven when he was not there indirectly their performance dropped drastically because there was no goal machine there.
But for now, I don't think it's appropriate to discuss something that is over, especially now that there is a substitute for Ronaldo who is still quite good, namely Dusan who is already there and puts on a pretty good performance for Juventus.