According to sentence 2.4.3, the number of solar-like star systems with planets about the size of the earth, in habitable zones, in our galaxy is 2.458 - 7.376 million.
According to sentence 2.5.3, the number of solar-like star systems in our galaxy, with distant earth-like planets in habitable zones, is 0.964 - 2.893 million.
Chapter 14 has shown that there are only a minimal number of civilizations. Thus, there are several million ananimate, earth-sized and earth-like planets from which raw materials could be obtained.

Then there are billions of planetoids, moons and asteroids that would be degradable.
When a species operates interstellar spaceflight, sourcing raw material from uninhabited planets or planetoids or moons should not be a major problem.
Whether it is about chemical elements, metals, ores, minerals, water, gases or even organic material such as wood, you do not need to approach (or conquer) inhabited planets.
There are enough uninhabited planets. And in some places even in higher concentration than on planets. There would be a reduction even more attractive. These include raw materials that would be interesting and accessible to us only in the future, such as helium 3 or methane.
Helium 3 could be extracted from lunar rocks in sufficient quantities. Methane and methane hydrate can be easily removed on Titan. And iridium, as well as the so-called rare earths, are likely to be much richer on some asteroids than on Earth.