Those percentages are not 10% and 10%. It's about where those percentages lie, and obviously we have different opinions on that. If you really think those are the percentages, I don't know what to tell you. If you're just being hyperbolic, there's no reason to talk about it.
There's also "catastrophic failure" on both ends. If the Jazz had followed this logic and traded Rudy immediately, they would have robbed themselves of a golden championship window. The point is to become a championship contender, not to acquire picks. You think the scenario where we improve is la la land, well I think the "catastrophic failure" where Donovan has an injury so bad it nukes his value is la la land given how unlikely it is. Is there something I don't know? Does he have a degenerative knee condition like Oladipo? I would not operate my franchise under the fear that any player could have a catastrophic injury out of the blue.
This Rudy trade discussion package isn't too relevant to the Donovan decision. I don't think you made a decision on Don because of what you get for Rudy. You could go any which way you want with Rudy. If he has no value at all and we literally cannot get a single pick for him, I think it's still sound to be patient with Don. If you don't think Rudy can get much, it's not like we can still get a ton of picks either. Getting a cornerstone piece from Rudy is certainly not the only reason why waiting can be beneficial or things can work out in our favor. Teams have waited out public trade demands and gotten what they wanted. The Jazz got nothing from Hayward and it worked out. There are many ways waiting can be beneficial, and the risk of Don's value dropping is low enough I'd be content to wait it out myself.
Of course I don't want Don to LeGM the franchise into obscurity. I do think you're suspicion is true that Don will be given too much power, but if we're talking about realistic scenarios, we shouldn't even be discussing the possibility of trading Donovan if he wants to stay. I'm of the opinion that having Don is a stronger position than not having him. If I was making the decisions, that's what I'd want to do. I'd be patient with the trade and I'd have no problem waiting to tank. In real life, where we're talking about Smith-Wade-Ainge as lead decision makers....yeah I can see how that could turn toxic as they bend the franchise to Don. Bending the franchise to Don is obviously not what I want, even if it is reality. I don't want to trade Gobert, but that is reality.
If you're frustrated about the upcoming decisions that are likely to be made, I hear ya. The first of those decisions is that we're trading Rudy Gobert just because Don wants to, which is really damaging for the franchise. This discussion about moving Don even if Don wants to be here (and after you already traded Rudy for him) relies on having some sort of control of the follow up decisions. It's a made up scenario, not based in reality and isn't something that will even be discussed, but it is an interesting conversation. I don't think my scenario will play out, because as you mentioned, the franchise will likely make rash moves to please Donovan. My desire, or lack thereof, to trade Don immediately is not based around pleasing him and convincing him to stay here forever. I don't think Donovan would stay long term with Utah if we won the title. His personality is what it is, and I can't see it. I don't think that belief means we must trade him now. While the real Jazz will likely make moves in the mindset to keep Don, I would be patient with the trade and not be in a hurry to tank simply because I think it's better asset management and team building.