Weighing in the day of the fight makes a ton of sense. It should be something the fans are made aware of as well during the "tale of the tape" segment. Fighter X weighed in tonight at 170-lbs. for his lightweight bout. That is important information. The CSAC is trying to stop guys from doing crazy weight cuts. Nurmagomedov, Till, and Tibau are three that come to mind, supposedly in excess of 20-25lbs. heavier on fight night. Important to note that you'll still be allowed to fight. Also important to note that fighters might not fully rehydrate until right before the fight which is another circumvention of the purpose of weight limits.
I guess it is nice for the fans and to be transparent, but at the end of the day seems kind of useless if the fighter is still allowed to fight and the only real repercussions are "you risk not be licensed to fight in this weight division for the future." So you may not have anything happen at all then.