In short samples, yes, it helps you to determine "luck" moving forward since HRs are fluke events by definition, BUT, in large samples, when your HR/FB is high as Porcello's, it tells you with 100% of certainty, you are a prone HR pitcher, and in this case due his poor command.
As BABIP and LOB, a pitcher can control this peripheral stat. How can you know? Large samples help you to figure out.
You can find career BABIP/LOB/ HR/FB rates significantly below/above the average, because some pitchers can induce/control (for good or bad) those stats.
This is FanGraphs HR/FB chart
Rating HR/FB
Excellent 5.0%
Great 7.0%
Above Average 8.5%
Average 9.5%
Below Average 10.5%
Poor 11.5%
Awful 13.0%
Porcello is at the bottom of the chart through 11 years. In his case this is not random/luck/fluke. He's been a prone HR pitcher.