There's a big difference between offering "end-of-life" versions for download, even if they are no longer supported, and forcing users on new versions even if they don't want to (which is fairly common for mobile/web apps and generally subscription-models like Adobe and Autodesk switched to).
That's because the world decided to adopt software as a service model, where your device is just a thin client and real work is happening on a server. And that model is incompatible with letting customers to run old versions.
I.e. exploitation pure and simple - delivering value to customers is incompatible with company exploiting those customers. This deserves as much pushback as possible, even though it seems like a quixotic effort.
But it is only a matter of time. Once webassembly achieves near feature parity with the native versions, you bet Adobe will switch users to the webassembly version.
From Adobe's perspective, it offers a lot of benefits:
- they don't have maintain build farms or pay a CDN to host GBs of binaries of native installers (for different OSes);
- users will always be on the latest (read: most secure) version since there is nothing to install or nag the user to check for updates/apply security patches;
- browser-dependence implies near-persistent Internet access, making license management/enforcement a whole lot easier;
- they can upsell you on cloud storage so that all your assets are available from any web browser.
