Professors are basically CEOs for deep-tech start-ups (at least in science and engineering). Yes, they know the theory, technology, tools, etc, (from their own time as PhDs and Postdocs), but they need to delegate much of the work to their team. Like a CEO, the PI's main jobs are to strategize (choose research direction), form partnerships (collaborations), and fund raise (find grant money). This money is used to pay said team (students) to work on the products (research projects). In this analogy, each student is basically a project manager working on their own product, sometimes with a MASc or UG student to help with the labor intensive parts (experiments). When the product is ready for release (publication), the PI helps market it (at conferences) and puts their name on it (as coauthor). This is not stealing credit, this is amplifying the team's success so everyone wins. It builds visibility and credibility for the team members involved, and keeps the ball rolling by allowing the PI to get more funding based on the win. Note that the PI is instrumental in choosing and guiding the work, leveraging their experience to brainstorm solutions when stuck, etc, but nobody thinks they are actually in the lab doing it all.

So, I guess my point is, a good CEO would eventually figure out if work is bogus, but they'll probably be the last to know. BTW, noticing the data problems when working on the draft publication is literally the first opportunity a PI would have to really see all the final data in one place. Conferences are 'low stakes' and it's not unusual to present some preliminary and/or partial data.

I know this opens a HUGE can of worms if you really think about all the repercussions (e.g. who really deserves Nobel prizes and awards?), but that's a story for another day.