You're definitely missing a few contextual parts of re-signing Trouba:
1. UFA years cost much more - Scheifele signed long term immediately after his ELC, so we're only paying for 5 or so years of his UFA years. Trouba long term would be nearly all UFA therefore, his pay will be relatively higher.
2. Scheifele's deal is an absolute steal. Any time you talk about signing Trouba, don't even bother thinking of Scheifele's deal. If we were to sign Scheifele today, do you really think he would accept 6.125M cap hit? His market value is probably 4M higher than that, so saying Trouba's set to get paid around 7M which is 3M less than a Scheifele level player isn't crazy.
I guess the moral of the story here is this thread has nothing to do with Scheifele and he shouldn't be brought up because he's in no way comparable to the Trouba situation.
Also, we would have to sign someone to a 14M deal to be in the realm of Chicago's salary situation. This argument doesn't hold water.
PS. Myers is not as good as Trouba. Opinions can be wrong, and saying Myers is better is wrong. "In my opinion, the earth is flat" is an example of a wrong opinion.