I am nostalgic of Commodore64 too.
The thing that made many of us go down the rabbit hole was the immediacy of the interpreter, begging you to enter some commands 2 seconds after turning on your computer.
The perceived small gap between the commands you enter in a programming language and the games you could play with the machine contributed largely to the curiosity and willing to learn more.
On a modern computer, building the right interpreter is challenging. There is a trade-off between the simplicity of the language and what you can achieve with it. You won't impress today's kids if it allows you to only print text on a scrolling page.
But I think one can build something really great. There could be an integrated sprite editor (with a graphic UI) and the interpreter can use them right away with something like: Sprite1.visible Sprite1.x = 10
emphasising again the immediacy. Those "sprites" could be 3d objects as well.