They're being downvoted because they're intentionally misreading what "pressured to perform" means in this context.
Both space shuttle disasters occurred because NASA was under pressure to 'perform' in the sense that they were under pressure to increase launch rate and cut costs to the extent that safety concerns were overlooked. Potentially serious issues were overlooked in favor of just flying.
Similarly, the concern here is that NASA management felt pressured to allow Boeing to put the lives of crew at risk despite serious safety concerns from engineers. While they would've lucked out in this case since they got to the ISS and have alternate ways to come back, if that turned out to be the case, it'd raise serious additional concerns for NASA's management of other Boeing programs (see: SLS and Orion).
As a taxpayer funded entity, NASA should feel pressured to perform in that they should feel pressured to progress their mission as efficiently as possible. This means taking the time to properly weigh safety risks, as a crew vehicle exploding due to known problems is a waste of taxpayer funds.
As the issues tend to build up at contractor interfaces, I would favor NASA to do more vertical integration, but, then, it'd need more funding, which won't happen if contractors such as Boeing and their own subcontractors don't drop the ball so much and if the press doesn't blame NASA for those.
The problem with that is historically NASA has used contractors to manufacture if not also design virtually all of their hardware. They don't have the experience to do it all on their own.
NASA wouldn’t need to be fully vertical, but it would be wise to have as few nested contractor interfaces as possible. This would make it have more responsibilities in integration of components from multiple vendors, but at least they wouldn’t be shielded from issues and would be able to see them as soon as possible.
Another important thing is that their jobs should be protected from political interference, so that nobody feels compelled to not speak up.
To a certain extent, this functioned exactly as how the Commercial Crew Program was intended. There were NASA engineers raising concerns with both SpaceX and Boeing and they would periodically be told to basically stand down because it wasn’t NASA’s place to direct the design since they were just buying a ride.
