Greetings,
Yes, that's the case. There are a few reasons for this.
First of all, no one wants to share their successful build for nothing. In the past, official events were held for this purpose. Unless very good players share their talent with you, any talent you find other than an officially verified talent will not be better or more successful than the one you made. Everyone creates something...
Why would anyone spend time on this? Making a build isn't just about sharing a talent tree. It requires a thorough explanation of the gameplay. If you don't know the skill order, a copy/paste build is generally useless for a player who doesn't know the class well. And every build is open to discussion, and the basic skills and rubies are already fixed; it's the little details that matter.
On the other hand there's no fixed number of rubies in the game. This makes it very difficult to create a build that works for "everyone".
There are many rubies available in the game (I think 18 pieces) beyond the rubies you automatically obtain when leveling.
Some of these are easily obtained from easy/early quest chains, while others require more difficult raids. And there are others obtained outside of World Mysteries. And of course, there are those obtained from chests, 7 permanent ones, and a few temporary ones.
If that's the case, how many Ruby's should be used to prepare a build?
And of course, everyone's build varies depending on their gameplay. In conclusion, Skill descriptions are very clear, build according to your own style, depending on the amount of ruby you have.
As you continue playing, you will be able to better decide which skills are unnecessary.