Until you stop off at the bar on a Sunny day and ride home on dusk once everything has frozen again, then you'd be like "oh I wish I didn't tell everyone not to keep their edges in decent shape", as you fly off the cliff edge.
On the real however, getting down the mountain safely after dusk etc with dull vs. sharp edges will likely only affect intermediate skiers. Beginner skiers are going to crash no matter what they’re riding if on steep and icy terrain. Expert skiers know when and how to ride conservatively and can basically ride anything in any conditions “safely” (even if that means just sliding a firm patch rather than carving it), as long as they’re aware of the limitations of their gear. 90% of the year I ride pow skis in any conditions (including melt freeze etc) with super dull edges - it’s totally fine. The other 10% is just to have a little more fun on very firm days.
Intermediates, on the other hand, will be overly aggressive beyond their capabilities. They’ll bounce their helmet off a melt-frozen knoll at first opportunity, similar to what you said!
The comment seemed like a "I don't wear a helmet because it's uncool" sort of thing...just do your edges occasionally, what's the issue?
Point being, I’ve never found sharp edges matter much for most recreational riding. None of this has any relation to being uncool. Maybe in your wifes scenario, having razor sharp edges would have saved her from breaking her arm; almost certainly not.
In pow and crud, I don't know if the edges do really anything, except if there was any rust, they'd probably grip the crud a bit.
That's also the biggest downside, you can't really rip it with fat skis. Not even if you go down dead straight.
On true ice, NO ONE is ripping it except racers or ex-racers with good equipment.