Do you think you know more about tech and its trends by using GNU/Linux?

I think it's correlation, not causation. Those who are generally curious and enjoy learning about tech are more likely to go out of their way to try and use GNU/Linux. Using GNU/Linux to browse social media, send some emails, and shop on Amazon isn't going to give anyone new found tech knowledge.

If we look at mobile where Android is basically Linux for the masses, getting an Android phone doesn't make someone more interested in tech. Most Android users I know just got the phone that was cheap or the person at the phone store pointed them to. They hardly know how to use it.

What do you mean? Windows users are uninformed about tech, whilst Linux users are more informed?

If you mean the general populace, then heuristically we can infer that Windows users may be less technologically savvy, but it’s not a given.