Yes. One can use a C++ library like Restbed and embed the web server directly into a compiled executable that uses SQLite as an embedded database. The "large-scale, multi-system architecture" in such common use today is completely unnecessary when faced with this setup. I have multiple Restbed integrated applications whose entire disk footprint is 7MB; they can run on a $99 Intel Compute Stick, perform industrial grade facial recognition with multiple HD video streams, and still overwhelm traditional web stacks with events and data when pertinent events the software needs to report start emitting over the wire.

The "only catches" are the developer(s) need experience working in multi-threaded C++, and they need to understand the traditional web stack they are eliminating.

What about fault-tolerance though? That's definitely a single point of failure scenario.

Run as many instances as your fault tollerance requirements needs. The expense of adding another physical box is trivial when that physically box is $99 to $250 total to own. They "pay for themselves" in their first month of use, versus any cloud configuration running any 'amp or node or Mean or simply "traditional" web stack.