20 minutes! You're an amateur! 
I have learned (and mostly forgotten subsequently) all about Scots royalty (prompted by watching the tudors at the time and wanting to delve back into the full ancestry and events before James vi and Mary Queen of Scots which I already knew a fair bit about.
Recently it's been history of board games, history of card games (but I STILL don't know how to play poker and I'd love to), history of make up....
History is a big thing with me but I'm also a huge film and tv fan and recently been watching west wing so been delving into not only that shows history and production and personnel (it's not just the cast I get interested in it's crew members) but also generally American politics and presidents and chiefs of staff and press secretaries etc
@HotPatootiebootie was just about to say that admittedly I have dx ocd and can obsess about the most random things and lose hours without realising - I have to set multiple alarms on phone and Alexa to tell me to stop reading/researching and eat/do chores etc
Your train of thought description is SO similar to mine! I know wiki isn't necessarily a reliable source of info but it's an easy starting point for many things and I'll start on one page...an hour later and I'm on my 50th page!
I even "play" connections in my head when doing stressful things "how did I end up researching z? Ah that's cos I started researching a and that led me to be interested or wanting to check on b which mentioned something weird about c..." and so on and so forth!
I don't retain all of it but I do a fair amount and I love quizzes. I'm housebound at the moment so can't go pub quizzes so I have to make do with my fixes of tv quizzes and trivia apps etc
I sometimes wonder myself how the hell I know a thing!
I once won a prize on holiday for remembering a random fact about a singers heritage, the act was a "tribute act" of the artist and said free drinks all night to the person who could answer which Native American tribe the main artist claimed to have heritage of and I knew! Only because I'd been reading about them in an ancestry magazine! Wasn't even an article on the singer but on the psychology of claiming certain ancestries and being in denial of others!
Mumsnet is especially bad for sending me off down a rabbit hole
Now I'm wondering if there's a particular name/pathology for this type of thought process I'm even half thinking I'll ask my therapist (she gets asked some really odd questions bless her
)
Mumsnet costs me so much in time (this) and money (products recommended, bargains etc)