The idea is mostly sound, but you shouldn't use 365 days per year since people don't work every day.

If we only remove weekends, we have 260 days in a year. Accounting for the average of 8 paid sick days, 15 days of PTO, and up to 11 paid holidays, we're down to 226 work days in a "typical" year. This makes the daily income needed to replace, e.g., a $100k salary $442 rather than $274.