I was also suspicious of Cloudflare as a full platform, but now it's one of my favorite ways to develop and scale web applications. I have implemented Minifeed[1] (and Exotext [2]) completely in Cloudflare Workers (except for the full-text search, for which I use a self-hosted instance of Typesense; though in my testing, Cloudflare's D1 database does come with full-text search enabled - it's SQLite compatible, and it works well!).
I also didn't want to have any kind of rich frontend layer, so all my HTML is generated on the backend. I don't even use complex templating libraries, I just have a few pure functions that return HTML strings. The only framework in use is Hono which just makes HTTP easier, although standard handlers that Cloudflare offers are just fine; it takes maybe 2-3 times more lines of code compared to Hono.
D1 is a fine database. Queues are fantastic for my purpose (cron-scheduled fetches of thousands of RSS feeds). Vector database is great, I generate embeddings for each fetched blog post and store them in the vector database, which allows me generate "related" posts and blogs. R2 is a simple S3-compatible object storage, though I don't have many files to store. Deployments and rollbacks are straight-forward, and the SQLite database even has time-travel when needed. (I've also tried Workflows instead of Queues, but found them unstable while in open beta; I haven't tried them after they became generally available.)
I know this might sound like an ad or something; I have nothing to do with Cloudflare. In fact, I couldn't even get through to the initial interview for a couple of their positions :/ It's just I always had this cloud over my head every time I needed to create and maintain a web project. Ruby on Rails + Heroku combo was probably the easiest in this regard, abstracting away most of the stuff I hate to deal with (infra, DB, deployment, etc.) But it was still not as robust and invisible, and also pricey (Heroku). Cloudflare workers is an abstraction that fits my mindset well: it's like HTTP-as-a-service. I just have to think in terms of HTTP requests and responses, while other building blocks are provided to me as built-in functions.
Minifeed has been chugging along for 2+ years now, with almost 100% uptime, while running millions of background jobs of various types of computing. And I didn't have to think of different services, workers, scaling and stuff. I am well aware of how vendor-locked in the project is at this point, but I haven't enjoyed web development before as much as I do now.
The only two big missing pieces for me are authentication/authorization and email. Cloudflare has an auth solution, but it's designed for enterprise I think. I just didn't get it and ended up implementing simple old-school "tokens in db + cookie". For email - they have announced the new feature, so I hope I can migrate away from Amazon SES and finally forget about the nightmare of logging into the AWS console (I have written step-by-step instruction notes for myself which feel like "how to use a TV" note for some old, technically-unsavvy person).
[1] https://minifeed.net/
[2] https://exotext.com/