No, "Universal" apps in this context means these apps can run in Mac OS, either on an Intel Mac or on an Apple Silicon (ARM) Mac. Nothing at all to do with iOS, iPadOS, Windows or Linux.
Isn't that misleading marketing? I know that companies can call their new efforts whatever they want, but if someone sells a "Universal keyboard" that only works with Windows, isn't that just straight up misleading marketing?
The only thing that comes close to being "universal apps" would be applications that run in a browser.