Compared with 1.17.1, the valley of the nether being filled with lava of 1.18 generated more and larger

The Bug

There is much lava in Nether.The lava valleys affect us to dig ancient debris.It'OK to have big lava lakes in the main world,but there is too much in Nether.We don't have it in earlier versions like 1.17.

1.17.1

1.18