Unlike a remote desktop, Puter is entirely in Javascript, where all the code runs on the user's local device, in their web browser. This makes it vastly more resource efficient than a full virtual machine (or container if you are using something like kasmweb), and thereby cheaper to set up.
It doesn't work for everything, but for the apps that do run a browser, like VSCode, it offers a much cheaper way to run those in a whole "environment" (rather than deploying them seperately). It's overall way less costly to VSCode remote into one server with 4 GB of ram, then it is to deploy a 4 GB ram instance just so there is enough ram for a GUI.
But wait! Why would a corporate product come with a variety of games for people to play? π€
That's because although this is a legitimate product, and a legitimate business, the true, actual usecase of Puter (and similar web desktop environments) is for students who want to play arcade games during class. Because of how efficient and easy they are to host, they can be hosted for free on a variety of platforms, allowing students at middle and high schools (12+ years old, but before college), to get around content blocking restrictions by rapidly migrating it from one hoster, ip address, or domain name to another if it gets blocked. This lets them access arcade games during class so they don't get bored.
Comparatively, the free VPS tiers often do not have enough resources for a desktop (plus gaming through remote desktop kinda sucks), and students aren't going to be eager to pay for stuff (have you seen AWS ec2 prices?!?).
Puter does not seem to have this (at least, not explicitly), but a very similar project, AnuraOS comes with a "web based proxy", that allows users to get around content filtering systems and view other sites that would normally be blocked.
There a source port of at least portal 1.
https://github.com/AruMoon/source-engine
Here's the active fork of the original project. Going through the issues of the original project, it seems to have support for building for 64 bit platforms.
No portal 2 support though. Although mentioned in the issues of nileusr's repo is this: https://github.com/EpicSentry/P2ASW , which is interesting