Playing games, watching videos, reading articles, etc. can indeed help you, but you need to keep learning, and you need some base knowledge to build learning on.
When learning a new language you start with learning vocabulary and simple grammar. Learning Japanese/English/… by switching the language of your media to Japanese/English/… without any other aids will make you learn very slowly, consuming media in another language to primarily learn vocabulary/sayings/…, basing it on your pre-existing knowledge can be very helpful though.

My English and Japanese are prime examples for this, actually.
In Germany pupils start learning English somewhere around age 8 to 10 in school (meaning: 2 or 3 times a week: 45 to 90 minutes of learning plus homework).
Starting at age 15 I actively started watching English let's play videos, putting what I've learned to the test. IMHO I think it helped me learning English a lot, so 8 years later I feel very certain, speaking English.

Also at age 15 I started watching anime in Japanese, with subtitles, without any base-knowledge to build on. 3 years later I could say simple sentences like "I am …", and I wasn't even certain about that.
2 years ago I took a Japanese course in University though, teaching me a lot in one year, thus now I can read and understand Japanese media, learning, while looking up stuff. The year of Japanese in Uni is a base of knowledge for helping me to learn when consuming Japanese media.

Gist of me rambling:
You need special media to consume, to also learn from, without having a "base of knowledge" to work on. Which the mentioned games seem to be thumbs up.