It's not so hard to find time. Many people with full-time jobs practice martial arts an hour a day for three to five times a week, while others practice a musical instrument for half an hour to an hour a day. Other people also complete part-time Master's degrees in highly technical subjects while working full-time (many programs like these are designed for full-time workers).
I've personally enjoyed language learning as a hobby, and found time in my commutes to listen to audio programs (I enjoy this more than anything else I could do on a commute in a crowded train, so it's no loss of time). For more casual gym-goers like myself, oftentimes running on a treadmill doesn't require full attention, so it's possible to watch video lectures or listen to more audio programs. Neither of these are as ideal as concentrated study in a quiet room with a desk, but they're relatively lower-effort ways to get useful practice with a specific subject (so it's easier to practice consistently).
I then find more time on the weekends for more dedicated study. If you're dating someone who also shares your interests in studying, they can also spend time studying alongside you (alongside more fun and relaxed dates).
To quantify this, that is about 13 hours a week of non-concentrated study (assuming a 1-hour commute each way every weekday for 10 hours, plus another 3 hours assuming studies during a 1-hour workout three times a week, at the lower end of how often you can consistently exercise). Add in another 1 hour of concentrated study a day (or if you'd like, 3 hours of extended study sessions each weekend day, plus additional scattered study during the week), and you hit 20 hours a week. You may not be as fast as the writer of the submitted article with this, but you can at least get pretty far from consistent practice over long periods of time.
it sounds like you have a good attitude for making smart choices about how you use your discretionary time. I feel I should just point out however that generalisations about how much discretionary time people have don't always apply as widely as you may believe. There's probably a certain bias to the "average" person you meet at, for example, marital arts clubs, as they're the people with that time. In other circumstances or phases of life people count their discretionary time in minutes per day, and that is probably right at the end of the day. Not criticising, just hoping to widen your perspective a touch.
I've personally enjoyed language learning as a hobby, and found time in my commutes to listen to audio programs (I enjoy this more than anything else I could do on a commute in a crowded train, so it's no loss of time). For more casual gym-goers like myself, oftentimes running on a treadmill doesn't require full attention, so it's possible to watch video lectures or listen to more audio programs. Neither of these are as ideal as concentrated study in a quiet room with a desk, but they're relatively lower-effort ways to get useful practice with a specific subject (so it's easier to practice consistently).
I then find more time on the weekends for more dedicated study. If you're dating someone who also shares your interests in studying, they can also spend time studying alongside you (alongside more fun and relaxed dates).
To quantify this, that is about 13 hours a week of non-concentrated study (assuming a 1-hour commute each way every weekday for 10 hours, plus another 3 hours assuming studies during a 1-hour workout three times a week, at the lower end of how often you can consistently exercise). Add in another 1 hour of concentrated study a day (or if you'd like, 3 hours of extended study sessions each weekend day, plus additional scattered study during the week), and you hit 20 hours a week. You may not be as fast as the writer of the submitted article with this, but you can at least get pretty far from consistent practice over long periods of time.