“High” isn’t an absolute number. Thresholds are relative.
To determine if you have a high AeT, you need another reference point, ideally anaerobic threshold (AnT). An aerobic threshold is solid if it’s at 90+% of AnT; “high” if it’s ~95%.
So for an AeT of 164, you could start adding a small amount of intensity if your AnT is ~182 or higher. (~182 is 90%; 95% would be an AnT of ~173.)
Was it a lab test that you did? Did the tech give you a number for AnT?
Or was it a DIY test? If so, here’s a DIY test for AnT.