It's bizarre to think, but it really does feel like some portions of the fanbase have become spoiled by the relative success of recent seasons.
From a personal perspective, I had seen us get promoted just once before Wilder arrived. Too young to know the joys of 1990, didn't attend a match until we were out of the Premiership. So for me, the majority of my time going to BDTBL has been disappointment. Lost play-off finals and semis, lost FA Cup/League Cup semis, and relegations. Just the one season under Warnock in ~20 years of attending games before 2016, where we actually won something. In contrast, 3 promotions in less than a decade, one of which we cruised to 100 points in League One. Multiple seasons in the Premier League (even if 2 of them were crap). It's such a different scenario to what I had become accustomed to.
The comparative deluge of good times we've had of late, especially at Championship level, make it so that when things do go wrong (even if only for 90 minutes), to some it feels like a complete disaster.
Unfortunately, I don't think there's a clear method to correct this manner of thinking, short of us going back to being mediocre again, and being stuck a league below the cloggers at S6 once more. Just have to remind people that, as far as Sheffield United is concerned, this is the best period we've had in living memory. So if we happen to hit a bump along the way, it doesn't need absurd reactive actions to put us back on course.
One defeat does not mean we should sack the manager.
One poor performance does not mean we should change the entire starting XI.
One bad day at the office does not mean our promotion chase is dead in the water (we're still second ffs).