So are unions and welfare and all sorts of things. A society that mixes and picks techniques that work the best is way better than the society that goes "well, capitalism has issues, throw it all out!" Marx was totally wrong about communism because people adapt to their situation. We didn't run out of oil by now because people found new sources and used less. We haven't run out of copper because we invented fiber-based communication. We are never stable as a society if you look at where we stand and extrapolate that trend into the future. What makes us stable is constant change and tweaking of ourselves. Our ability to deal with instability is what makes us stable, not the fact that our society is made to be stable.It's a prop to keep capitalism from running off the rails once society no longer carries the structures that made it a stable social arrangement.
I'm saying that one of the conditions that capitalism springs from is wage labor. It's perfect for a system that uses price to allocate resources. Unions fight to strengthen wage laborers. Welfare provides them with a basic social safety net. They augment wage labor. Automation is coming. It isn't augmenting. It's replacing. Maybe we get UBI. That creates a new social class. Maybe we don't. That swells an existing class that started this discussion. Either way, it's going to be quite a large change. Societies are a process, yes that process seeks stability, but every so often they hit an inflection point and tip in a new direction. That's what gave rise to capitalism in the first place. It is a process that stemmed from a change in the patterns of human activity. "well, capitalism has issues, throw it all out!"