Yea my first playthrough I heard you could get the icon by sailing relatively far from him, so I sailed around a neighboring island and got it easily
However I later found out it wasnt the norm. On my current seed, if I didn't use the Valheim map generator I'd have been looking for him for hours, the closest was in a random remote island and too far inland to be detected from the shoreline.
So when I start a new seed it's ridiculous: I check the seed on the map generator, check the trader icon and wrinkle my eyes as to not get spoiled of the landscape (cause that's part of the fun for me) but able to see enough just to get a clue of the bearings of its location...
I think a hint as to where he is could be nice. Like a compass or something

Using cheat sites is never a good idea, find the Trader or Bosses by playing the game and searching the biomes.

Here a "how to" the legit way
https://steamcommunity.com/app/892970/discussions/0/3105766250718433330/

I alway check the islands that surround my spawn, the problem is that seeds like this are not so rare.
Map [valheim-map.world]

WIth over 500 Maps i checked i had only 1-3 such cases

In one game I found him on the first island I sailed to, and that island was just a short karve hop from my base.

In another game I sailed around for many, MANY in-game days, in all directions, without ever finding him.

I'm not actively looking for him in my current world, but I hope I've gotten a lucky seed in that regard as well.

The map site I will never use for my worlds. Exploration is much more fun and rewarding, even if (or especially if) it takes a very long time to find the trader. The world is finite, so it's only a matter of time and luck.