By that age, I was into my third long-term job (> 5 years) and had had upwards of 16 short term ones - multiple part time ones at once, or some just for a few weeks or a couple of months here and there between the long-term ones etc.

48 doesn’t seem that unlikely - nor even an indicator that they will not be staying put for any length of time unless your job is a shitty one with a high turnover anyway.