Well, to decide whether "sprints" are a good thing or not, you have to consider the history, which is mostly centered around the alternatives.
"In the Beginning, there was Waterfall" -- prior to the era of agile practices, waterfall was king: first, gather requirements, then, design a system based upon those, then implement that system, then test it, then deploy it, then maintain it. And write volumes and volumes of detailed documentation about all of these steps.
While there is nothing really wrong with waterfall per se, it tended to annoy people greatly, due to delivering irrelevant software and tons of irrelevant paperwork in many (if not most) situations. Because unless you're, like, building a moon landing guidance system, "the business" tends to change too much between the requirements and deployment phases. And/or: the "requirements" people were simply not very good at their jobs. In any case, pretty much everyone was unhappy with the end results.
So, at some point, there was the "agile manifesto" movement, which tried to fix this from the side of both the "business" (which felt it was spending too much money all the time) and the "developers" (which felt they were doing pointless work all the time). The four main points of the movement were and remain:
(1) Individuals and interactions over processes and tools
(2) Working software over comprehensive documentation
(3) Customer collaboration over contract negotiation
(4) Responding to change over following a plan
So, right away, most of your reservations about "sprints" seem to be negated by principle #1: Trainers, books, seminars and rigid CI/CD are not prescribed by capital-A-Agile at all. It's about you, your team, and what you decide to do. Of course, this may very well mean you should look for a different team, but that can happen due to many, may other reasons.
"Artificial deadlines" are, in my experience, mostly a commercial issue. A "sprint" is always a fixed amount of time, to be spent on development. If malfunctions and associated maintenance take time away from a "sprint", that should be covered by a support/maintenance agreement. If the same people work on both development and maintenance, the former should be paused while the latter takes place. So, a 2-week "sprint" may very well take 3 or 4 weeks, if interruptions take place.
This takes some adjustments in contracts, sales, etc. But I can assure you, that a "2 week sprint of uninterrupted development time" coupled with a "maintenance agreement that extends any development sprint by the time required for personnel to fix and re-focus" works quite well. Sure, some sprints will end up taking many weeks but that's all time that's paid for, and nobody will object to payment in the end, provided all is agreed upon in advance and backed by time-sheets afterwards.