Now that it has either been inadvertently fixed, or made much much more difficult, I’ll let you guys in on a secret.
Nether portals can be used for teleportation prior to the 1.15 update.
How to: Enter the portal and there’s a sweet spot while it’s loading the other world where you have to completely close out the game. (Red “X” , or force close/crash)
the game used to load worlds before updating your coordinates, so if you hit that sweet spot, you’ll go from 1000, 70, 1000 over world to 1000, 70, 1000 nether. Go to over world and you’re at 8k, 8k. This is a very very fast way to get out to 100k or farther.
BEWARE!!! There may be rocks/lava/holes and other dangers at destination. Always store valuables and carry a fast pick in hand to keep from suffocating. Then build your corresponding portal for the return trip in the opposite world.
After some practice, it’s easy to hit the sweet spot timing-wise... I’d say 5 out of 6 times. If you miss, it’ll just put you in the other world as if you never left the game.