"I’ve worked remotely my whole career"

Regardless of all the perfectly valid reasons for being unhappy in what most people consider a cushy job (the author seems perfectly aware of that), this could possibly be an important factor here.

Working remotely means you only get a small slice of what most people get out of their job. Again, this is perfectly fine if you're not "most people", but if you've never known anything else than that may play a considerable role in being dissatisfied with having a job.