From 1,000 page views per day to zero in 9 hours

I'm freaking out a little. I run a large site (~2 million pages) that I prepared to have Google index about 2 - 3 months ago. The preparation process mainly involved setting up server-side rendering, making my pages mobile-friendly, and fixing any page speed issues. Google has been slowly indexing my pages and as of today, about 250k pages have been indexed. I've been thrilled with the progress that Google has been making, and I have slowly seen my organic traffic climb from 0 to about 1,000 page views per day over that 2 - 3 month period.

Early this afternoon, all organic traffic stopped. I have seen absolutely no traffic from google in 9 hours. Does anyone have any idea what could be happening here?

I have over a year invested in this project, and I have this sinking pit in my stomach telling me I'm looking at the beginning of the end.

Some other details:

• Because my organic traffic push is new, my backlink profile is weak (currently <5 backlinks). I'm positive that this is not an issue of google invalidating the link juice of a large portion of my backlinks.
• 99% of my traffic is generated from long-tail keywords; of the 250k indexed pages, even my top-performing pages would only receive a couple of hundred search impressions (not clicks) per day. The vast majority of my traffic comes from pages that receive less than 20 impressions each day.
• My content is derived from multiple publicly available datasets. While a lot of processing does go into the content I produce, I do have at least 2 competitors that produce content from similar data sources, and there are instances where I could have blocks of text that are identical to my competitors (as a result of sourcing a portion of text from the data set)
• My content is objectively stronger than my competitors as they set up paywalls in front of certain portions of their content, whereas I do not. According to Ahrefs, my competitors are receiving 500k - 1 million page views per month (albeit with much stronger backlink profiles than I currently have).
• EDIT: I have also confirmed that this is not an issue with google analytics.