Agreed it is an avalanche effect, up to a point. From the private key perspective, but not the public key perspective.

Meaning, normally, if you have the same number of leading public key characters, they often will hash to the same leading characters in an address.

I was recently reading this, somewhere.

However, the private key is the wildcard. Trying to match the first x amount of characters and it hash to same public key or address is not the norm.

People like to tinker. Nothing wrong with that. Their idea may spawn something that helps solve quicker. Maybe, maybe not, but it doesn’t hurt anyone from a person tinkering out their ideas.