As they say, the more things change the more they stay the same. I'm in agreement with Robin on that one. I can only speak about from when I joined, but I think that wasn't too long into the life of SRP.
Ducks were and still are popular. Pumas were the rage a while ago too. Big old wedges have always been favourites as well. In fact in my view very little has changed on the razor front with the exception of a marked increase in the number of (custom) makers. Back when I first joined there were very few, and most of them were in their early stages - Bill Ellis, Joe Chandler, Papabull, Maestro Livi come to mind.
Honing? Again, not much has changed. There is still some kind of mythical shroud that covers the honing world. When I first joined there was this weird thing going on where forum kudos was linked to (self-proclaimed) honing ability, and people were vying for the "honemeister" title. I think because Lynn was one, and people wanted to be like Lynn but am not sure. You'd see funny things like someone come along in their first post asking all these newb questions about honing, and then within 6 months would suddenly be the new honemeister on the block, setting up shop refusing to hone wedges or do resto honing because they were too hard... come to think on it, not much has changed there either!
Hones have changed IMO a lot. Very limited range in the synthetics back in "the day", or at least very limited knowledge of the useful ones for razors. There was a bit more knowledge around about the naturals - coticules and thuringians in particular were well-known, though recent years have shed much more light on the various kinds of coticules and their accompanying price-points. Back when I started a coti was a coti. Man were we (and our wallets) an ignorant bunch!
But now of course the synthetics are everywhere. Again, when I started it was all Norton 4/8. Everyone was setting bevels and doing resto honing on the 4K, maybe lower grits if you were lucky to find one. A lot of us were either shaving off the 8K side or the real fancy-pants went onto a pasted strop (CrOX mainly). Some of the lucky few had a (gasp!) $200 Escher thuri. Some really rare birds had these weird Japanese naturals that clearly would never take off as they were too fiddly to use and there was next to no information about them. And they were ridiculously priced.
Strops haven't changed too much either - the materials people use is probably about it. Let's face it, there's not a lot you can change with a strop besides the leather type.
Soaps and creams, and brushes and aftershaves etc? I never cared too much about the "software" side of things, so I never paid too much attention to the trends. But I do think they are mainly trends with good ones standing out and remaining constant over time. Castle Forbes is one that sticks in my memory. I'm sure Martin de Candre will be another.
So there you have it - a grumpy middle-aged man's view of the world of (forum) straight razors. Now git offer mah lawn!!! :p
James.