OBS vs other certs in this field — is it worth it salary-wise?

Trying to decide whether getting my (OBS) Online Boating Safety Certification is worth the time and money investment. I've been doing research on "OBS" and the salary data is all over the place.

Some sources say it adds $5-8k/year on average, others suggest it's more of a requirement to even get considered for certain roles now rather than a pay bump.

Has anyone here seen a direct salary impact from getting OBS certified? Or is it more of a "required to apply" thing in your industry now?

Also — how long did the whole process take from starting to study to passing? And what was the exam fee in your state/country?

Trying to do a real cost-benefit before I commit 5-8 months to this.