Don't worry. The comment that surprised you is not really true. The 81k figure is for "overtime-exempt" employees (often just shortened to "exempt"). I.e., if you make less than that, you are considered "overtime-eligible" (opposite of exempt), and in that case, if you work more than 40 hours per week, you have to be paid overtime. Also, the 81k figure pertains only to software people. There
is a figure for other occupations, but it is much lower.
There are also differences in how business travel is treated. Overtime eligible employees have to be paid for all time spent in transit, but exempt do not get extra pay. (Of course, in both cases, travel expenses will be paid by the company, I am speaking of pay for travel time.)
In fact, the 81k figure is a marker and not a bright line. The actual separator between overtime eligible ("OTE") and exempt employees considers several factors, including job responsibility and experience.
The OTE/exempt distinction has become more rigid in recent years because of lawsuits by attorneys representing low-paid (e.g 60k/year range) employees who had been considered "salaried", and asked to do extra work for free (e.g., the travel time mentioned above) because they were salaried. These suits resulted in the distinction between OTE and exempt shifting.
If you ask me, it has in general hurt very early career engineers making 70k per year, because they have to account more strictly for their time than before. For instance, they cannot redistribute their hours between work days the way salaried employees can.
(Only speaking of California here.)