If you can land a job like those at PARC or Bell Labs, then yes, "carreer hacking" is certainly possible. Considering how many IT professionals there are now and how few there were back then, I'd say those kinds of jobs are even more scarce now than they used to be.
It's not impossible, but it's not a realistic expectation.
> If you’re devoting a third of it to something completely unrelated to your passion
A programming job is likely to be as far from any kind of hacking passion as any other, with the added disadvantage of possibly poisoning the well, so to speak.