The game is perfectly playable solo. You get to make unilateral choices on where and how to build. You can advance your progression as you are ready; no need to rush to keep up or slow down to wait for others. You only need enough materials to meet your needs. Meanwhile, you can listen to the soundtrack without being interrupted.

Playing with others can also be a good experience; it just hits differently. If you don't have friends or a group on hand to play with, there exist places online to find others.