Yes, hello to you, too!
Actually I have been a user of the forum in the past, but did n switch to the new forum until now.
In formZ 6 or older it was hidden in the draft workspace.
When you switched to draft and used the select by tool you had the options for this.
I think many useful things from v6 or older still have not made it into the formZ 8. (Like the possibilty to transform multiple selected objects individually with the transform tool - i.e. have the transormation being exectuted relative to their respective axis)
About the usefulness. If you are able to have multiple line styles and want to switch the styles of certain lines, how could this not be useful?
Why have styles at all, if you can´t work properly with them?
Imagine a drawing (could also be imported) with several linestyles. You want to change some objects from dashed to solid style. Right now the only way is to delete the dashed style, and select solid as a new style. But this affects also objects on hidden or locked layers.
The slect by tool could use a couple of more selection options. (it used to have a script option). Like selections of certain faces (normal direction etc.) and the possibility to save selection sets other than objets (points, faces and the like)