I'm not sure what the parent post meant exactly, but I do agree there is tons of grunt work -- I've seen big name SV companies where large parts of their work flow include parts like "and then just every hour you need to do something in a slow UI that can't be automated" to keep vital systems working. I would say that's really grunt work, and there are even persons in such companies where their only task is doing such grunt work. Truly I've been told by clients I work with they have entire double-digit sized teams where the members only responsibility is to reboot VMs that breach specific resource thresholds -- easily automated and even built into most hypervisors, but for whatever reason these tech giants opted for a human to do it -- the only semi-reasonable explanation I got from one client was that their infrastructure team got outsourced and they laid off the only people who knew how to use the automation tooling. It's a dumb reason for sure, but at least I can understand why they opted for the manual grunt work.

Similarly, keep in mind a lot of this grunt work is just to satisfy some reporting requirement from somewhere -- some person(s) in the company want to see at least X% of uptime or Y LOC every day, so you get people trying to write a lot of yak shaving code that basically does nothing except satisfy the metrics or ensure that uptime % always looks good (i.e., they don't fix the cause of the downtime entirely, they just get the endpoint that is checked to determine update working well enough so it reports to the monitoring system and they leave it at that)