I'm sure Taco is viewed as a total bust across the league.
Why are you so sure of this? I can imagine several teams who might think he got stuck behind DeMarcus Lawrence, and hasn't get a real shot at being a player for the Cowboys. Just because he's not a RDE doesn't mean several teams wouldn't be interested in bringing him in as a LDE for a reasonable price. I could easily see several teams that pick in the 48-57 range who might be willing to trade back in order to get Taco, plus a 2nd round pick if the player they think the player they want would still be available at pick 58. Yesterday, Denver traded down from pick #10 to Pick #20, and still got the TE they wanted.
I appreciate that some are frustrated with Taco, but he was drafted to replace Lawrence BEFORE DeMarcus had his break out season. That's just bad luck for Taco, who was always projected to take about 3 years to develop. That doesn't mean Taco doesn't still have talent to be a valuable member of a rotation. It just means that maybe it won't happen for him in Dallas. Another team could easily come to the same conclusion, and decide they could get a bargain in trading for him by moving down a few spots in the draft.
The Cowboys got a steal in getting former 4th overall pick Cooper for the 27th pick in this draft. At the time, some Raiders fans had soured on Cooper, and mocked the Cowboys for giving up so much. How does that look now? On the day Charlton was drafted, I said his long-term upside was akin to a Justin Tuck or Tony Tolbert type career. I stand by that assessment. The reason fans are disgruntled is because their expectations were too high to begin with. That's not the fault of Charlton.
Based on gossip reports, which are inherently unreliable, it may be that Charlton has a bit of an attitude issue. But even if true, that may stem from him not getting the chances he was expecting to get. A move to another team might solve that problem for him. So, just because he might have been a wasted asset for the Cowboys doesn't mean another team doesn't still place value on him.