What are the advantages of using postgres? It makes radarr/sonarr faster?

Yep Cloudflare protects against classic DDoS (like many clients doing a lot of small requests). Here attacks are performed presumibly by users that know very well how the Lemmy’s backend works and where bottlenecks are, so that with a small number of well made requests they are able to mess up the backend and Cloudflare doesn’t notice it