I worked at an ISP for a while where we set up a projector display and just had the log firehose on the wall at all times. I never really paid direct attention to it, and it had terrible resolution and a lowish refresh rate. Even still, the human brain is an amazing pattern matching machine and the feed gave us a lot of useful insight. Regularly someone on the team, even non-technical folks, would walk by and say "oh looks like $customer is having problems" just because their brain had divined a pattern from exposure and correlation. Sometimes we could turn those moments into automated alarms, sometimes we couldn't figure out how our brains made the determination.
To this day I still try to keep a log feed visible along with the grafanas or whatever - it is shockingly useful even if I don't ever read those logs on the display.
I have done that though, where you just let loose the firehose, and scan for patterns during some nasty event.