The moment you finally meet someone interested in discussing one of these things, its going to be immediately apparent the basis of your knowledge is a brief article/book or a weekend watching videos on youtube. Furthermore, these are all going to be little self-contained treatises without any prerequisites -- they are written for a general audience, so you are completely limited to, as the article describe it, the appearance of mastery to people who don't know better.
That's only if you insist on explaining things to everyone you meet. If you're smart about it, you can quickly recognize an expert and take the opportunity to ask them questions. I have had many discussions with experts in fields for which I knew only the scantest of concepts and terminology. I begin by asking questions and proceed to go deeper and deeper into the subject. It's amazing how happy people can get when you show a genuine interest in something they care about.
By arming yourself with a "Wikipedia summary" of each topic, you have the starting point for very interesting conversations. Don't let the article's title get to you. It's far better to be someone who is interested in everything than it is to just "know everything".