You mean any assessment is baseless, ONLY when taking into account FT%, right? Bowiac says he's seeing no "signs of improvement" based solely on the same metric, but he also admits that he's never seen the guy play a minute of basketball. I think HRB is trying to say that there is more to the story than just free throw percentages and/or three point percentages. I think you would admit that a guy shooting 30% from 3 point land with nobody defending him is likely much worse a shooter than a guy shooting 30% who is constantly double teamed and has hands in his face, no? And that's just one example. Not every percentage has equal value, and when we're talking about a sample size that is as relatively small as Dunn's, I think folks need to look a little deeper than just the numbers to determine if he has actually improved. Watching him play would be a pretty good first step.
But then you go a step further, and say that based on these percentages (if you've cited anything else as a reason for this belief, let me know), you literally have no reason to think he can get significantly better? Really? In his age 24 season, there was an NBA player that shot 13% on 3 pointers on 52 attempts. After a couple of up and down seasons, he shot 37% as a 26 year old on 245 attempts, and then 27% as a 28 year old on 100 attempts, and at ages 32 and 33, he shot 42% and 37% on 260 and 297 attempts, respectively.
There is another guy who shot 31.9% and 31.5% at ages 22 and 23 (both over 300 attempts), and had an eerily similar to Dunn, range from the FT line at 69%-71%. At age 28 and 29, his 3 point shooting had gone up to 40.6% and 37.9% (again, over 250 attempts each year), and his FT shooting had gone up to 75% both years.
Obviously, the first guy on that list is Michael Jordan and the 2nd is Lebron. Both of whom were pretty dreadful shooting the ball early in their careers, but by the time they were in their late 20's, had become pretty damn good. I just don't know how you look at a college kid (regardless of age) and claim he's hit his ceiling, or that you have no reason to believe he can't improve, based on nothing more than looking at his shooting percentages without any other context at all. Of course he can. Guys do it all the time, including some of the all time greats of the game.