Actually, It depends on more than that: the skill of Federal Detectives to find and get key people to co-operate, the skill of Federal Prosecutors to argue these cases convincingly in front of a judge/jury etc.

Lawmakers are required to pass reasonable laws and regulations, but these are often provide guidelines. Antitrust laws were written in response to specific issues with monopolization, and many Big Tech companies have managed to skirt around them by interpreting its provisions in specific ways.