I only felt the trunks were problematic when the reasons for it as time moved on into the modern world kept getting smaller and smaller until it didn't have any reason to exist anymore. The redesigns were great (hell, even what they had in mind with the Superman V films were fine), from the comics to other media, and you all know the the DCEU suit is as timeless as the classic suit, so they did a great job there.
If there are a couple flaws in those redesigns (other than the belt that Romita, what the hell man), it would be the KISS rule they forgot (KISS=Keep It Simple, Stupid) because there are fanart that took the classic suit and removed the trunks only, and you felt was a better choice that going overboard. And the the fact that they changed one thing, but then they changed another which was unnecessary. The Rebirth suit was great, but why change the boots? I changed them back and they felt right. So those would be the flaws.
I will say this: Doomsday Clock is set a year into the DCU, and the books will be leading toward it. It was pointed out by ComicPop that they believe Johns wants that series to be timeless, so when we saw the yellow oval coming back on Batman (he doesn't have trunks on), they said that made sense because you want alot of people to read this story from the past and into the future and see a familiar Batman they know. So maybe that's why the trunks are back on Superman.
But for them to go back to the trunks hasn't settled in with me. While I do like the classic look, I never hated it mind you; like I said above, the reasons for it decreased over time, leading to the redesigns that were as important as keeping the core of what needed to stay and what was identifiable with the character of Superman with this costume.
Also, I said this before and will say it again: of all the things about the character to fight for, fighting for his underwear on the outside is one of the dumbest fights to have.