The last paragraph in the OP was meant to be satirical ... the OP author has lots of experience with Agile -- which has morphed far from its roots as a set of succinct principles laid out by real engineers who understand true software craftspersonship.
The problem is is Agile, is turned into an entire industry of its own with multiple philosophical streams, that in some cases borderline on religion. There's a huge financial interest in keeping this industry alive and thriving.
Project management has existed for a long time and SAS as used at variously,. The complexities and pitfalls of building "correct" software have been understood since Fred Brooks wrote the edition of The Mythical Man Month, roughly 50 years ago.
In my observation Agile is often seen as a panacea, but if we can "just get it right" and do sprints and scrums on the right intervals then it will be effective. In reality, it has another administrative layer functioning as agile professionals, who think they have answers for real engineers, who understand how to design, build and validate Software.
It is also been pointed out that CI/CD is not necessarily the best model SAS considering the majority of the paying customers still run on premise. Some of those customers are chafing at being forced to deploy Viya 4 locally in containers. The trade-offs and conflicts of trying to streamline software delivery, and maintenance of course demand that all of this is standardized in containers.
There's no need to even address your git comment because of course it has become the standard way of doing source management, versioning, etc. That said, apparently, Google doesn't use it internally.
You are spot on and pointing out that there are many reasons why SAS is currently in the shape it's in. My generation build the core SAS products and saw the company grow from roughly $50M annually to well over $2B before any of the technologies, we are currently discussing became relevant.
It is indeed, unfortunate that the transition to the current way of successfully operating a software company was not done with greater care. The biggest dilemma I witnessed was a general complacency in many (certainly not all) longer-term R&D employees to take a leadership role in this transformation as well as corresponding conflicts with more senior developers and managers brought in from the outside who had experience with more modern techniques.
Then there was the ever present need to deliver new releases and maintenance of our existing software while attempting to also involve the build/test infrastructure. I witnessed one Director level manager, literally shaking and having a meltdown over the stress of all of this. He is a highly conscientious individual and was working day and night doing his part to make the transition successful. Thankfully, he was able to move to an individual contributor position before the leadership role destroyed his mental and physical health
SAS R&D was built on a very unique and highly innovative culture going back to the late 1970s. Honestly, if anyone commenting does not have experience dating back to pre-MVA code and then the entire history of MVA and TK, then they can't possibly understand just how hard the problem of transitioning to a modern cloud-based CI/CD delivered product is when the whole of SAS (especially some of the highest revenue generating pieces) is taking into account. The UX pieces are the proverbial tip of the iceberg. There is a world of code underneath based on some of the best computer science and applied math. You will find anywhere. Yes, it's aging. Yes it's being displaced by open source, cloud, vendor, offerings, and newer tanks on analytics, AI, etc.. Yet, it was one he-l of an effort and one that I'm damn proud of habe been part of.
From my vantage point, agile is mostly a superficial bookkeeping system (associated with a set of high-priced tools) that has very little to do with real Software Engineering. If doing SCRUM or Kanban or whatever works for your team, then do it and adjust it until you get it right.
However, that's not the same thing as deep thinking about real engineering/deployment problems and creating effective strategies for how to solve them. There is not an agile coach or scrum master who has ever help me improve on these things.