I don't know what people expect from the 16th pick. He's shown improvement every year (both visually and statistically), is a major piece of a championship contender (6th most minutes, 4th in advanced analytics), and could be the starting PG on a good amount of NBA teams in just his third year. Is he John Wall? No, but it doesn't mean that he sucks.
Tommy Point for you - glad to see people actually looking at Rozier's play in context.
You're looking at a kid who practically did not play during his rookie year (due to him being buried behind a backcourt that was already 4 deep (IT4, Smart, Turner and Bradley) - and even in his second year his minutes were sporadic and role was never clearly carved out.
Rozier's a kid who has always played better the more minutes / opportunity he's gotten, and his shown consistent steady improvements every season. There's never been any reason to believe he couldn't take a leap if given the opportunity - he's just never had that opportunity until now.
If we didn't trade out Bradley and Crowder, he'd probably still be buried deep on the bench looking like he did last year. Hell even if the Hayward injury never happened, we'd probably see Smart / Tatum getting all of those perimeter minutes off the bench and Rozier wasting away.
He's a talented kid who has always had the ability, just needed the opportunity - the trading of Crowder and AB, along with the injury to Hayward (unfortunate as it was) has give Rozier the opportunity to step up into a more consistent role with more consistent playing time, and he has taken a huge step forward in development as a result.
Look at the Danny's decisions so far - trading for Thomas, trading for Kyrie, drafting Brown, trading down for Tatum, the Brooklyn trade. I think it's safe to say by now that Danny Ainge is nothing short of a basketball genius - and a basketball genius who's proven that he's never afraid of making moves. And yet he's downright REFUSED to consider including Terry Rozier in any trades so far - that's got to tell you something about what he sees in this kid.