Ryan Tannehill hurt his knee in his fifth season and that ended his season early, and that knee ultimately cost him his sixth season. Also let's not pretend we are talking about a perennial pro bowler since his rookie year with division titles and play off appearances to his name. So far Tannehill has zero pro bowl appearances, zero all pro, zero division titles, and zero play off appearances (maybe he would have got us the results Moore did to end 2016, then again he could have blown it like a previous season). That means Tannehill is replaceable because he's never emerged as anything more than a good middle of the pack quarterback.
So like I said, if this front office believes that an available quarterback offers them an upgrade then they should take them, even if it means developing them over a season or two behind Tannehill, then trading Tannehill and giving the new QB the reins.
This team isn't a QB away, then again, depending on your view of Tannehill we might also not have a true franchise quarterback. And until that vacancy is filled, this team should always consider drafting a quarterback.