I've never had a job explicitly tell me that I could just go read, but I've done just that at multiple jobs and no one has ever said anything about it.
Of course, with work from home, things are different, but I'm still at the mercy of the time-tracking system: every hour has to be accounted for and charged to a pre-approved bucket... and reading isn't in one of those buckets.
No offense, but have you ever tried politely telling such people to fuck off?....
...something rather common in the UK, though part of me suspects this would offend American sensibilities.
I find this mind boggling.
Here in Blighty, I've never had a job where taking time to research and read up wasn't expected. Personally, every employer I've had has also allocated several days a year to staff training; either classroom training or self-study as needed.
Never had a job where the answer was yes, which is a shame, because that's still by far the fastest way to really "get" anything. They'd much rather I spend weeks googling one-off questions and wasting other people's time than being "unproductive" for a few days just going through actual documentation. Very frustrating.