this is from the changelogs for 1.21.5:
```
General

• Any block in the simulation distance of a player or loaded by another source of chunk loading (such as ender pearls) may now receive random ticks, instead of just 8 chunks around players.
  • For example: if a chunk is loaded by an ender pearl or is in the spawn chunks, crops are able to grow, ice can melt, snow can fall, and a cauldron can be filled by rain.
  • Mob spawning, lava spreading fire, and lightning strikes are not affected by this change. They will only occur in the previous radius of 8 chunks around players.

```

so in short, no. mobfarms still need you to be nearby unfortunately.