I don't think you have to worry about anyone changing their vacation plans because of reading our opinions on these threads. Most people are smart enough to know that these threads are not official websites representing the cruise lines.
OTOH, if information on these boards does motivate somebody to change to a more sutiable option, that's a good thing. The people who do change their vacation plans proably end up where they will be happier!
Before booking their cruise, newbies will have talked with their TA's or with the cruise lines directly. Both Agencies will explain at the time of booking the cruise lines guidelines regarding dress. For their first cruise, most newbies will be excited and looking forward to their FIRST formal night. They will attempt to abide by the requirements. (just like we do)
It's only later, when they've cruised a couple of times, and they begin to have other expectations from a cruise experience that they may begin to question the whole dress code issue. Before that...it's most likely NOT an issue.
Unfortunately, there are some travel agents who will tell potential clients anything just to close a deal -- and that's reprehensible. Rather than representing each cruise line's dress standards accurately, they might tell clients that "well, Alsaka is more casual so you'll be able to get away with a sport coat and tie on the formal nights..." while pitching a cruise on a line like Celebrity, for example. That is, of course, a real dissservice to (1) the cruise lines that they misrepresent, (2) the other passengers on the misrepresente dlines who booked in good faith expecting certain standards to apply, and (3) the people to whom they made the msirepresentatoin, who are stuck on a ship that's a gross mismatch for their lifestyle without appropriate evening attire.
BTW, I understand that some cruise lines are now attacking that problem at its source by paying commission bonuses to travel agents who consistently book passengers that are a good match and penalizing travel agents who consistently book passengers that are mismatches trhough reductions in commissoins.