I haven't played "Pac Land" personally, but from what I've seen the mechanics and design look totally unrelated to the original Pac-Man game.
That apparently came out only a few years after the original, but whether or not it's a good game in its own right, it does appear to be an early example of creating "sequels" based solely around the "characters" rather than the gameplay mechanics of the original- the same thing that led to the modern, soulless Pac-Man-in-Name-Only game that the author decries.
In fact, apparently the graphics in its US release were based upon those in the Hanna Barbera Pac-Man cartoon. (Which I remember being a fan of as a kid- I think before I'd ever actually played the original Pac-Man game- but doesn't look that great to me now!). So *that* was a sort-of-spin-off of a cartoon as well!