CAPM and PMP are not the same rung
CAPM is the entry credential and expects no project management experience, though it does require formal project management education. PMP requires substantial documented experience leading projects and is the one that changes salaries. Conflating them is the commonest mistake here: CAPM opens a door, PMP is what people mean when they say the certification is valuable.
Predictive and agile both matter now
Exam content has shifted to cover both traditional phase-based delivery and agile approaches, which reflects how organisations actually work — most run some mixture. Preparing for only one leaves a real gap, and in practice the judgement about which approach suits a given piece of work is more valuable than fluency in either.
The part the exam cannot test
Most project failures are communication failures rather than scheduling failures. The exam can test whether you know what a stakeholder register is; it cannot test whether you will notice that two teams have quietly assumed different definitions of done. That judgement comes from doing the work, which is why the credential is a beginning rather than a qualification.