Has anyone noticed low-authority, zero-backlink, low-word-count content ranking for high SEO difficulty keywords?

I have noticed a ranking shift in my project keywords on Google over the past two days. Some unknown competitors are now ranking on the first page, with one even in the top three. The SEO difficulty of these keywords is between 40 and 50. After checking the domain authority of these pages, none exceed 10. Interestingly, all these pages have ZERO backlinks! What could be the issue? Am I the only one facing this issue, or is this happening across the board?