Yes. If Turang reaches that stat line that I previously posted as his prospective ceiling, he WOULD be a borderline all-star, and should not be traded for a rental like Bell. But we don't know that he will become that.
Like most prospects, he probably will not reach that ceiling. I would guess that over his first 6 years in MLB, his 6 year slash line would MOST LIKELY look more like .240/.330/.380 (with good defense, speed, lefty-stick). Still a legitimate big-leaguer, but pretty replaceable. If they trade THAT player for Bell, I wouldn't lose sleep over it. But as I previously stated, I'm not sure Bell is even worth it. If the team is dead set on "going for it," (whatever that means), then they need to trade like they mean it. They need to trade whomever it takes to get a guy like Soto/Reynolds/[insert superstar here].
That would not be my preference, as I think I'd prefer that they simply sit tight this year (probably an unpopular opinion).