GT identification looks at some additional data points so it's worth completing the form and having that data available. Being identified as GT doesn't put kids into classes, but as a PP noted, it can be helpful when you are advocating for your student to receive enrichment. The form only takes a minute, not really any downside for you.

He could get into AIM and HIGH based on test scores and grades — schools have the discretion to pull more kids in. This state-mandated GT designation is not particularly meaningful, but if he is identified it would be one more reason to point to as to why he should be allowed into those courses.

I've gotten a ton of notifications that I need to do the parent form for rescreening of my 5th grade kid for gifted/talented. The kid didn't make the pool for the magnets. Could he get into the AIM and HIGH classes in middle school off of this?