You actually kind of have liberalism wrong as well though. It's the idea that individual liberty creates political agency. From that we get the ideas around inclusive society being critical to a functioning democracy, because democratic participation is the intersection of inclusion, liberty and individual actualization.

Or rather, people must first be free to engage with political questions out in the open (liberty). Then they must feel like they have a stake in society (inclusion). Then they must have the time and resources to participate (actualization). This is the foundation of liberal democracy.

What you are describing is commonly considered a form of liberalism, but is more aptly described as progressive liberalism. You are definitely correct though, that many forms of leftism and liberalism are compatible, despite people on Lemmy insisting otherwise.