These are all false arguments.
First, nobody ever said that Smart was better than Turner, but that's not a prerequisite for him stunting Smart's growth. Turner was better than Smart offensively, but there's still no doubt that he stunted Smart's growth in the ball-handling and play-making context with his ball-dominance and primary duty as the second unit ball-handler. Should we not develop any of our young guys whatsoever unless they're "better" than the guy in front of them holding him back, even if that guy in front of us is only a stop-gap replacement for the present? No. I understand why we had Turner in there, but the fact that Smart "wasn't better than him to earn those duties" does not mean that he still was not stunted in his growth by Turner's presence.
Second, you must be remembering a different game, because Rozier and Smart shared the ball-handling duties pretty evenly in the second unit when Turner wasn't in there. And I'm not sure where you're getting this notion that Rozier getting minutes was some highly beneficial thing for the team. I like Rozier, but the only reason he got minutes was due to Bradley's injury. He came in and played good for a rookie, but it was hardly anything that you're making it out to be.
Third, the only thing that I can take from this past season and postseason with regard to how Stevens views these two players is that he thinks Smart is much more ready than Rozier due to him giving Smart 27+ minutes a game in his rookie year and Rozier only 8 minutes a game in his rookie year.
You're displaying a tendency toward recency bias with Rozier's summer league play, but that doesn't mean he was doing anything like that during the season or playoffs.
Sigh. None of these are 'false arguments', nor am I exhibiting 'recency bias' in regards to Rozier's summer league play, which I wasn't impressed with if he's going to be used as a point guard, moving forward, nor did I even bring up how he did in Vegas, etc., so I'm not sure from where you're getting that idea.
In regards to your other points, I fail to see how Turner hindered Smart's growth, at all. I get that Evan is the better passer and ball handler, but don't forget the number of times when Stevens was experimenting with lineups and we had players hurt and Smart was entrusted with running the second unit and he was awful, quite frankly. Furthermore, Smart could have helped himself by, idk, moving without the ball or posting up, given his height and size advantages on most guards, but aside from a game or two, he never got on the block, probably because he doesn't really have any moves down there, a great fake or two notwithstanding, iirc. Smart should have improved at something, anything, by now, but he's still the same player that he was at Oklahoma State.
Additionally, not once did I ever say that Rozier getting the primary ball handling duties was 'highly beneficial to the team'. All I said was that he had been entrusted with that responsibility over Smart, so, again, I'm not sure how you arrived at that conclusion. However, let's say that I'm wrong and that your premise that Rozier and Smart 'shared' the ball handling duties when Turner wasn't out there is correct. Does that not tell you something about how Stevens views Rozier, who hadn't played at all, really, during the year, as opposed to a second year former 6th overall pick who has gotten about 27 minutes per game since his entrance into the league? I get that injuries played a part in why the rotation was so discombobulated during that series (of course, had Stevens played Rozier and Hunter, etc., during the year, he would have had two steady contributors by the time the postseason rolled around, but I guess that they weren't 'good enough' to 'earn' that playing time

, but let's not open that can of worms, lol

), but don't you think that if Smart, who has always backed up both guard spots, was so far and away the better ball handler and passer, etc., not to mention player, that Stevens would never have had Rozier on the court in the first place, never mind sharing said responsibilities as a rookie in playoff games?
Finally, what do you see Smart becoming, as a player? A backup, key rotation/role player, starter, or an all star? I'm assuming that you think that he's the latter, right?