You need a real cushy job to get enough time and energy for the second job that would be the research. And a tenure-track position usually comes with some work

You need a real cushy job to get enough time and energy for the second job that would be the research. And a tenure-track position usually comes with some workforce or at the very least a good network of experts to refer to. There are of course really shit academic positions, but you'll anyway not have time for research if you have a really shit job, so that objections seems to cancel.