My observation on the slopes is that many if not most people here in the PNW are on skis that don't match the terrain and conditions they're on the majority of the time. For example, a few years back I was seeing a lot of Rossi S7's when there wasn't enough fresh snow to justify them. Being open minded I demoed them in two different lengths and neither felt right for the cut up crud off-piste, and neither held a decent edge on piste. So my reaction was, "what was the point?" Even on a bonafide (no pun intended) powder day, the fresh snow gets tracked out really fast and you're left with heavy cut up crud. I found the S3 better suited for mixed conditions.
So I started instructing the last few years, and noticed that a lot experienced instructors were on E88's and similar other skis, whereas newer instructors (particularly younger one) were on Armada TST's, which may have a pretty good edge hold for a 100-ish ski, but not nearly as effective as a narrower all-mountain ski. I also noticed examiners and clinic leaders on Head Rallys and Titans. And they could crush the variable conditions better than the younger instructors on TST's. Now, most of the instructors I know also have wider skis for when the conditions call for it, and they're not afraid to use them
If I am marketed or sold a pair of wide skis, I am not being done a disservice. I'm pretty sure I could benefit from a good pair of 110-115 crud busters. Ski envy is a serious disease….sigh.
That said, I think the real issue is whether wide skis are being oversold to aspiring skiers who are buying their first new pair. It depends on the store. Some shops and salespersons have the integrity to help someone find what's most appropriate, others just got to sell whatever's got the buzz and selling like hotcakes. Can't always blame salespeople, they need to sell product and if someone comes in asking for the latest highly rated and reviewed ski, they would have more work to do to convince that person to buy something else.
So do I care what other people are buying? Nope. Where's the harm? They can happily tool around on whatever they want, as long as they stay in control (I know, sometimes that's a big "if"). At some point they may realize they want a frontside-ish ski. More sales to keep the businesses happy.
However in lessons it's much easier for me to teach someone and help them progress when they're on the appropriate equipment for the conditions. If they ask about skis I will share what limited expertise I have and suggest a visit to a fine ski shop in their area and or look for demo days.