When a government agency (think IRS or FAA) decides on a specific interpretation of a law, rule or regulation, they don’t go after a random guy to prosecute. They publish an opinion, a guideline, or interpretation and a compliance deadline. The industry is given a choice to comply or present an alternative interpretation (through courts, lobbyists or legislative representatives).
It’s one thing if one company out of a hundred doesn’t comply, and somewhat different when the standard industry practice goes against new interpretation.
Selective encorcement is more typical of countries with weak judicial systems and endemic corruption, where “friends” of the current government get compassionate understanding, but everybody else is subject to the strict rule of the law.
