everyone learns in different ways, don't be too attached to your own perspective. we all interpret the world through different lenses and need to learn through the expressions of different methodologies. some people benefit heavily by implementing something themselves and not just reading through something someone else wrote. some people feed off of that practical and robust experience of implementation in order to get a proper context for how things actually work established in their head. concrete examples are more helpful than you might think to people who aren't as capable of abstract thought and logical analysis of something from its constituent parts

Your approach is 100% valid, but it can't hurt to start making a really small lisp. Of course the implementation strategies of a "MAL" lisp and a Real Lisp are entirely different.

Other people have different preferred learning styles.

A toy language won't teach the exact same things, but it covers a lot of the same topics.

Perhaps you could write up the process you followed, in the form of blog post or something, so that you can pass on the knowledge. I, for one, would love a guided tour through those implementations to see which parts are worth studying to understand how an established Lisp is built.

I don't have the time to learn it that way. It's this or never doing it at all.