Aside from scrum being a rigid process, and therefore not agile, adoption of scrum is essentially adoption of a 20-year-old agile, where sprints are 2-8 weeks (like the agile manifesto says). But agile has evolved since then, especially since the advent of DevOps.

Scrum, Kanban, &c. is a complete irrelevance. Most of these processes—and some are useful—are orthogonal to agility. When a process is imposed or you feel obligated to "follow the rules," they’re much worse, of course, moving you in exactly the wrong direction. Allen Holub on Twitter

The title of this article is sort of odd, because the very idea of "agile" is flexibility. But that's the point, I want to emphasize the flexibility of agile. One of the core concepts in agile is the idea of "Responding to change over following a plan". This can't be overemphasized. Customers/users expect resilience, and the ability to change their minds.

I've noticed lately that a lot of folks don't understand why certifications matter, or should I say, matter in a negative way. As a developer, if you obtain a certification, it's important that you don't put it on your resume unless the organization you're applying to is asking for it. There are many leaders who throw resumes out when certifications are on the resume. They don't do this to be smug, they have very good reasons for this.