The Aroldis Chapman return will almost certainly never be replicated in the history of this game. That was exclusively a one time deal. So, we were never getting Hassell, who was the key part of the Juan Soto deal. Juan Soto's value eclipses Hader's by an almost infinite degree.
And the tweet you are referring to was completely made up. There is no indication that the Brewers were ever in on Soto, nor should they have been with what he eventually went for. We will always need a farm system, and trading for Soto would have completely emptied ours, not to mention taking guys like Ashby off the MLB roster.
You say you miss Doug Melvin... Well, have you even bothered to compare their two records? 4 (potentially 5) playoff appearances, including game 7 of the 2018 NLCS vs. 2 playoff appearances, including several woeful seasons....