I took the DL specialization and it took me a while because I worked really diligently through every single thing and made sure I understood before moving on. It was purely for self knowledge and the certificate was super tangential to my aims. I noticed later that basically all notebooks were copied and out into GitHub and it would have been trivial to simply copy and paste all answers and get a certificate.

That made me pretty convinced a cert wouldnt be worth much, which is unfortunate because I really put in the work to learn the material. OTOH, I largely consider certificates to be a bogus signal, and even often negative, so that not really surprising.