I've been at Tesla a long time and I probably don't know anyone with 5+ years under their belt who isn't either completely jaded, or else has completely drank the kool-aid. The dividing line arises roughly between manager/senior manager, or staff/senior staff.
Right below this dividing line there's a universal feeling of being unable to get adequate support (lab space, equipment, hires) to improve the status quo, because of a complete absence of mid-level employee empowerment, artificial scarcity, and executive hubris that we are all super smart and talented and can out-think any problem, never actually needing to scale up our test capabilities to handle said problems, (as doing so obviously would suggest we aren't super smart.)
I've seen countless staff-level employees quit over this, getting frustrated being stuck without anywhere to grow (especially if you're not a kool-aid drinker), being denied resources, but still kept on staff...why?
"Just in case" we ever decide to start listening to those talented 5+ years experience PhD staffers, I suppose? I have frequently thought about quitting over this same issue that caused so many of my former colleagues to quit.
Management always paints a blue sky picture at every company meeting, getting very excited about the latest thing and long term growth prospects, but remains starkly untrusting of engineers who suggest anything's not going well, providing lip service suggesting you can simply come up and talk to them (director+ level with fully booked schedules at all times). But then when you do go up to this person, I have found no earnest intent for collaboration.
They are quick to wave away your concern and do not promise any sort of resolution or path forward, even when you present them with a tangible and justified plan of action. In this way, management acts as if being frugal in the test lab is a perverse victory for the company rather than an enormous liability.
We've been shifting to more and more of a program management culture, scaling the number of cell programs, by several fold, and exponentially growing the cell supply, while scaling support to the core technology by a mere fraction of that.
In this new culture, program managers are responsible for task managing a lot of the "old ways" that were haphazardly established back when Tesla actually did have resource scarcity. Those old ways were wrought with false premises, but many engineers still demand running those same tests because (especially for newer employees) it's all they know, or (for old timers) they did speak up about it many times, but management would disingenuously tend to ask if there was any data to prove that a new proposed test would work to alleviate the problem, despite not actually helping to provide a pathway or resources to allow exploration of that very question.
These grandfathered-in bare bones tests were arguably necessary for scaling the company in the early days, but should've only ever been attempted with the promise that eventually we'd do things right once we had the resources. Instead, we doubled down on these old ways, assuming they work great (even with evidence to the contrary) and we often cannot even adequately execute on that.