Summary:
There is no /gamerule commandModificationBlockLimit in Bedrock. In Java Edition 1.19.4 it has been introduced, but didn't make its way to Bedrock.
https://www.minecraft.net/article/minecraft-java-edition-1-19-4

Added commandModificationBlockLimit, controlling the maximum number of blocks changed in one execution of clone, fill and fillbiome

Steps to reproduce:

1. Enter a world with cheats on.
2. Go to chat.
3. Type:

   /gamerule commandModificationBlockLimit

Observed results:
There is no /gamerule commandModificationBlockLimit in Bedrock.

Expected results:
It should be there in Bedrock as Java Edition has it in Java Edition 1.19.4.