I've yet to see examples of "agile gone right" outside of folklore.
I work with multiple groups at any given time and all of them end up following many of these patterns. Through one proxy metric or another, agile systems become bad accounting and metric systems that are used to pressure developers to the point of burn out and or leaving.
For management, the goal is to push more efficiently from a fixed salary. From their misguided perspective, they're already paying you $100-200k+, so they own all of your time. The more they can get you to do over 8 hours, the less they're paying per unit (hour) of labor. This leads to high turnover, burnout, poor products, and is ultimatelt passing costs off to employees.
At some point, for many, time investment vs compensation can even out to working a fulltime and decent full-time and part time job (12 hours a day). The employer has managed to disguise this through all sorts of deceptive means. The employer may be ignorant that fact, they may (genuinely) think they're just pushing you to work a full 8 hours or so, but it's more common than people seem to want to admit. And ego in software development and widespread imposter syndrome for newer developers just perpetuate this problem.
New developers won't admit when a request is absurd, they assume they're slow and pickup the slack. They also are trying to gain entry to the market so they're willing to sacrifice their time in hopes to jump ship for a less toxic environment with higher comp to time ratio. "This is just temporary." Ultimately, that mentality creates an expectation and experience only buys you so much efficiency in certain situations. Those new developers provide positive reinforcement to business managers that "this is the way."
As that happens at more and more enviornments, work to life balances become toxic at more and more places and the end result is, those new developers may never get a chance to escape that toxic balance because they've enabled it, everywhere, through fierce competition of ego.
I learned this at my first job when a very senior (nearly retired) developer working in development since the punch card era seemed to only be producing a little more than I could in a day. I thought, well he must be barely working, lazy or incompetent because I'm a newbie and not too far behind him. "This guy supposedly helped contribite to the development of quantum theory, write some of the first computer simulations for this, and friends with nobel prize winners? What a sham, his skills must be so dated!"
So for awhile, I started churning out more progress than him but he never changed his pace. At some point I realized I was investing a lot of extra time for no apparent reason. I didn't get paid more. I got some "brownie points" but ultimately, I realized I was undercutting my manager and mentor by using my free time and at the same time, creating an expectation of my production rate that required more than 8 hours of work. I was sprinting in a marathon and only harming myself by trying to be competitive and show I was as good or better as this relic developer. It turns, out I was just unwise, and he was light years ahead of me at setting realistic expectations. Through the rest of my career I realized he had created the most realisticand accurate time estimates for development timelines I've encountered and created a work environment that was well balanced for everyone and kept his boss happy, all while no one was stagnant and still developing professsionally.