For example you can write your portable app in Node.js (with or without containerization) and push it to a "serverless" PaaS, without running your own linux machine or worrying about k8s.
e.g Fly.io, Render, Railway...
Do you really feel that serverless is somehow faster than a reasonably modern computer?
Nodejs on a single machine can manage tens of thousands of connections if not hundreds of thousands.
The vast, vast majority of sites would never be able to consume 50% of the computing power in a modern gaming OC.
I would still do it in AWS, as it is like golden garden, don't need to deep dive into security measures, to manage authorizations manually, to handle database sharding and optimizations, you get notifications systems, ML, data streams and everything just connects together.
From there using lambda is way faster than to develop your own api with caching and making sure it is 100% optimized so that 10 thousands ppl can connect, while in fact you might change it tmrw.
I am pretty sure this is way more expansive to spend engineering time making it possible for server(s) to scale using kubernetes and stuff, than just using serverless.
And later with many users, we estimate what better be implemented manually to save money, because at this point it would actually save us money to employ a new engineer than continue paying serverless due to number of users.
Don't you think serverless makes sense?