What has helped me the least is code quality and GitHub projects/portfolio. This has only helped me in the added technical experience and the ability to talk through a variety of scenarios during an interview.
Interesting, I've interviewed with and for a number of tech companies and it's never come up. What companies are you seeing who are interested in certs?
This year though things have been far more competitive. I wasn’t getting interviews at all until I focused on a combination of my development experience, my TS, and my certs. Since then I have had many interviews and several competing offers. In one case I given an offer to write test automation in Java with 0 years experience writing Java at this big rocket company, I do have experience writing test automation utilities though. I have since taken a work from job on API architecture for this massive data enterprise.
I've met multiple interviewers who said if you know the material, you wouldn't bother with a certificate... For them a cert is an anti-signal for competence in getting a job!
That said, I'm now working on completing Terraform cert. I know the material well, but missed a question in an interview. Investing time/energy in fleshing out my knowledge for the cert will be helpful, even if I don't mention _having_ the cert at all.