Yes, there *are* tens of thousands of folks successfully using SL every day of the week. We call them 'uncommon'. And it isn't about the lowest-common-denominator either. The Lab says 90-99% of folks don't make it through those first 6-10 hours. If you're technically adept, you're less likely to be one of the folks that make it -- why that should be is a matter that's still open to debate. Almost every survivor says that they already knew someone or met someone who helped get them through this period.

In this case, how you'd use a box of toothpicks in SL varies from creator-to-creator, so instructions *would* be necessary. One of the things that takes the longest for people to grasp is that everything is third-party and the operation or use of third-party items varies independently of appearance or type. A vehicle might be sat on -- or it may need to be worn like an accessory (or both). It may use pop-up dialogs, or require a separately attachable HUD. It might need to be clicked on by the owner first, or it might not.

After you've been in SL for a while, you acquire the necessary grammars of interaction that you are rarely phased by this sort of thing. You can look at something and figure out fairly quickly what the most likely methods of operation are.