Because Dongsen belongs to the kind of game that you play for a while when you have time, or surf the Internet for a while every day. If it is a cassette version, and you happen to be playing other games at the same time, inserting and pulling the cassette will be very complicated, which will make you lose the courage to start and may gradually eat ash.
The physical version of Dongsen (that is, the game card form) is hard to buy now, but the digital version can still be downloaded.