Single-vendor open source is the balance some companies have found between sharing their software with the community and capturing the value of their employees' labor. It's less free than openly developed FOSS and more free than proprietary software. It's unrealistic to expect all software to be openly developed FOSS with today's economics; the hundreds of thousands of contributors to single-vendor open source projects all need rent money, and you can't build a business on providing the open-source backend for AWS managed services.
Companies will move up and down the freedom gradient depending on their needs at any given time. Sometimes they do it well, and sometimes they handle it in a kludgy and myopic way (I'm looking at you, HashiCorp). LinkedIn open-sourced Kafka, and Elastic restricted their license for ElasticSearch. Software doesn't always go from "more free" to "less free."