I mean, not necessarily. Civilisation for an alien species could look completely different to what we expect. They might not be carbon based. They might experience time very differently from us. For example they might experience time the way a tree does, or a blue whale, and thus do everything very slowly. They might have no interest in a Dyson swarm and instead be interested in something else. Who knows? If humanity decided to colonise the galaxy who's to say that within a million years we wouldn't have 1. Changed priorities (such as if AI reached singularity and had different agenda to us, or developed a new spirituality)

2. Evolved differently

3. Found a new source of energy, perhaps being able to unlock dark energy for example, which would mean a Dyson swarm is unnecessary

4. Turned on each other and slowed down the Dyson swarm expansion by fighting over control of different parts of the galaxy

All sorts of interesting concepts! :)