If you think about self-isolation from a different perspective, it’s like we’re all in slightly less severe Biosphere. And that, in a sense, is like astronaut training.
In 7.5 billion years, the sun will likely swallow the earth and nothing will be left. If humanity and its far far far descendants are to make it, they will need to leave the earth. We will likely need to leave the earth at some point within the next few decades.
What self-isolation will likely help us in realizing is that we can be stuck in a confined space for many months and manage. This period is cultivating the next generation of astronauts and Mars explorers.