Job seekers almost never actually know if the job was real or not, so it's hard to see how Glassdoor reviews can ever provide the insight this work is looking for.
I do believe that "ghost" jobs exist, often for H1B purposes, but I don't think this work proves it.
(Currently waiting for "final decision" on 2 interviews which went well, but after 3 weeks, I'm starting to feel they're ghosting me)
From the other side, they may be evaluating more candidates, hoping for a better fit. From the same side, I accepted an offer with another company after waiting for weeks for Google to respond, only to have them finally get back a couple days later. Someone dropped the ball on their end. Another interesting aspect is that I was laid off 4 weeks into my new job, only to then be hired by the team I was embedded with 2 weeks later, which goes to show you that large corps can be disorganized, so while one team is trying to hire to meet demand, the larger org is planning cuts to the workforce without giving them the heads up, while another part of the org is expanding with permission