This new feature (which I've already gotten to test), I can almost use the same way, though I'm wary of Mozilla yanking it away from me if I rely on it.
At the very least it'd make managing 100+ open tabs more feasible.
But now with advancements like tab unloading/discarding and faster CPUs, it might work for some people om mobile devices. Desktop browsers though might still be hampered by limited task/context-switching options.
The feature is still in the OS, so apps that declare support can allow users to open multiple simultaneous windows of itself. Most native Android apps can probably add support for this feature with minimal code changes, as Android "best practices" have pushed apps towards good reactivity support and rigorous handling of app state in these types of edge cases.
On Mac, it seems that all the major applications are using the standard keyboard shortcuts for tab navigation and I don’t think that’s very different in practice to what you describe. I assume Windows is the same?