Is there any sort of possibility that this mod will be updated/ported to more recent versions (1.16-1.19)?

Funny you should ask that. I was outside weeding and started thinking about that question.

The short answer is yes.

The long answer is that there's three options to consider, which aren't necessarily mutually exclusive. Since 1.13 the forge hook I used to implement the mod was deprecated, and I couldn't figure out how to update the mod using the built in mojang structure gen system.

I also tried using datapacks, and it's possible I could make a vanilla jigsaw version. I did a proof of concept and it kind of works. I'm sure with enough effort I could actually make an okay datapack version.

The other option is to create my own hook (via mixin) that replicates the old method I used to implement the mod procedurally. I've already implemented the hook, and it works. The problem with doing this is that it's considered wrong by the modding community and I'm not sure it's worth the complaints about recursive chunk generation.

I've been tempted to just update the mod the "wrong way" because I just want the mod to exist in a modern version so I can play it myself. But this would take a while.

Those are my thoughts on it. Really I'm in the same place as the rest of you, I'd like to play this mod in a modern version, but the modern way generation works forces me to either get flack for doing things a "wrong way" (the way it was in the past), or to do it the modern way which puts some pretty harsh limits on my creative freedom, assuming I can even figure out how to build structures in code the mojang way.