He's much more polished. Dekkers was a kid who had played QB his entire life because he was the best athlete as his small school. He had great measurables but was still an athlete learning to be a quarterback. Those measurables gave him a lot of potential but coming out of high school, he was more like Joel Lanning than Brock Purdy. Higher ceiling/lower floor type of guy.A lot has been said about Rocco's demeanor and leadership being an upgrade, but he's flat out a better QB than Dekkers. His physical ability is still underrated by our fanbase. He is very accurate and has plenty of zip. More importantly, he sees the field and understands the game better than Dekkers. He does have the benefit of a better offense under Scheelhaase, but Rocco has P5 ability already. This isn't a Kyle Kempt story.
Becht had some huge advantages growing up as the son of an NFL player. He received the best coaching, attended football factory private schools and obviously having a professional player/coach/analyst for a father helps. He had a 3 or 4 year head start on being college ready. The game is much slower for Rocco.