SkyBlock

Not impossible but you cannot make it to the end from what I have seen.

I was able to make it to the nether and found that it is just the regular nether, not a void as I was expecting.

TBH I enjoyed the challenge of just having lava and ice.

If you are curious how I was able to make it to the Nether:

I built a mob farm and smelted the golden armor/weapons to get golden nuggets. Used those to get a Golden Apple. While getting golden items, I was able to find a zombie villager and a witch. The witch throws weakness potions so set up a system where the witch would hit the zombie villager. I used my GAP and had me a villager. I made it into a farmer and sold it my carrots that I had also gotten as a drop from my mob farm. Using the emeralds from there I waited for a wandering trader to get some dripstone so that I could make a cauldron and get some more lava. Several hours later, I had enough lava to get a nether portal going.

In the level.dat file, I made all the ground blocks air, so don't worry, there is space everywhere :)