I don't think that those 4 prospects (or any prospects) are ever really untouchable, but at the same time, I don't believe they should be touched right now.
If, for the sake of argument, we were 57-43 right now and felt like we were one SP and one big bat away from being the AL favorite, then anyone is on the table in the right deal.
But we're not 57-43. We're 49-51 and clinging to playoff relevance, so yes, there are some guys that are "2026 untouchable"
But at the same time, I'm going to disagree with some people in this thread that don't want to see ANY assets moved away at the deadline for marginal 2026 improvement and are still interested in the idea of selling assets. I understand your points. I just don't agree with that philosophy under the current circumstances. I believe that:
There are difficult to quantify benefits to having your franchise play meaningful baseball in September and October, and
Generally speaking, odd stuff can happen over small samples (the playoffs).
If the threshold for pushing our chips in the middle is "I think we're as good as the Dodgers," then we're never pushing.