Do you see how painting Jed as overly conservative in his spending, to the point you say Tucker is "clearly not going to be here in 12 months" is at odds with also painting Jed as making a "last ditch attempt to save [his] ass" in trading for Tucker? Not that you can't make multiple types of mistakes, but the underlying behavior motivating those moves(overly conservative, reckless to save his job) are essentially the opposite.
This is what I mean when I say that his flaws are whatever people want them to be in order to be mad at him, because at a minimum you are dramatically underselling the odds Tucker is in Chicago in 2026 and beyond. Nothing is guaranteed, but teams who earnestly try to keep top of market FA under the qualifying offer have a very good success rate, and Tucker getting to play on a good Cubs team undercuts some of the more common reasons it doesn't work out(an uncompetitive team, a tiny market, etc)
But to the Tucker decision specifically, you never get the chance to make the perfect move, and that barometer of being a 'single move away from the world series' is arbitrary and counterproductive. The Cubs right now project as the 3rd best team in the NL and the clear favorite for their division. Every season matters, not making decisive moves while you have a core in place for the next couple years is frittering away the good things that have happened to get the team to this level, just because it's not a guaranteed long term deal or that the team doesn't project to be a 95 win monster doesn't mean that you can't make moves that prioritize next year more than the 2-3 years afterwards.
I don't love every move Jed has made this offseason, in particular I was not without reservations in trading for Tucker because of the cost and what pressures it put on the rest of the offseason. Like Bertz, I think he's being a bit too risky with the rotation given Wrigley is likely to revert away from being an extreme pitcher's park. But I also can see how there's a path to things working out and tradeoffs from having gone a different way. If you honestly are thinking that Jed is a 'moron' and 'can't for the life of you see how anyone could see the point' in trading for Kyle Tucker, have a little more curiosity.