/tick can't be run by command blocks and datapacks

Steps to Reproduce:

[1]: Place a command block

[2]: Put something like "tick rate 4" in the command prompt

[3]: Activate the command block with Redstone, or however you set it as

Observed Results:

The tick rate doesn't change with the /tick command in the command block

Expected Results:

The tick rate should change if the /tick command is in an activated command block