In all the many ways that the hobby of stamp collecting has changed in the last 50 years, probably the most significant has been in the de-emphasis of the "great buy" that was at the heart of philatelic writing in previous generations. Everyone wants a good deal and to get what they pay for (and maybe a little more), but most collectors today are happy to get good value when they buy and don't hope to find an Airmail Invert every time they go to the post office. This change is more significant than most may think because it has happened slowly. Fully half of Pat Herst's great book "Nassau Street" written in 1960 is about great deals that he made. And while the stories are interesting, they are his great deals, not ours, so our interest after a while seems a bit prurient and his ethical standards somewhat low. Oddly, Herst's ethics were considered sterling in his day, but by modern standards he seems to have cut ethical corners and often engaged in questionable promotions and deals that most dealers wouldn't engage in today, let alone brag about in print.
Certainly ethical standards in philately are higher today, but so too are the standards about bragging over "finds". And finds are far less likely now than ever before for two reasons. First, barring some major mail house holding that is lurking somewhere, all of the great commercial stamp hoards like those of the archives of the great trading firm Frederich Huth (sold by Robson Lowe in the 1950's) have been dispersed. Second, scanning and Ebay have meant that even better stamps or specialty items left in lots and unknown to the seller no longer slip through the cracks to produce great deals for knowledgeable buyers who had an opportunity to view the lots. This was no doubt pleasurable for the buyer, but what was usually glossed over in the older days was the financial loss to the seller.
One hundred years ago, collectors and dealers sold counterfeits without really caring. Fifty years ago, major dealers like Herst believed in Caveat Emptor. In our time, Apfelbaum is a bit ahead of the curve with our lifetime guarantee of description and genuiness (no other dealer does it), but in another fifty years this level of security to collectors will most likely be routine. Perhaps everything hasn't gotten better in the world, but security for stamp collectors certainly has.