Regulations, a lot of times, tend to have the opposite of the intended effect. In this case, you'd need to define what is meant by "having data".

Is having an email or phone enough to qualify?

Maybe yes.

In that case, think of a rapidly growing startup, which breaches that mark (50% or whatever the law says) - and now has to comply with the law.

But the startup is not capable of compliance, because the law was made for behemoths like google.

This startup will go belly over and die soon.

Google's monopoly saved.

Alternatively, leaving it in the public domain for civil suits to be filed has a tendency of natural selection. If a company is TRULY big enough, and has that kind of data, someone WILL sue.