The Software Freedom Conservancy legal analysis of RHEL and GPL that OP links to is the most interesting part to me. https://sfconservancy.org/blog/2023/jun/23/rhel-gpl-analysis...
You can use others' GPL code in your products and charge money for it. You have to "publish" the GPL'ed sources (and any sources of yours that derive from GPL'ed code) on demand -- publish as in: if someone asks, you have to give it to them, but there's no requirement that there be a public download page or anything like that, and you can send the sources out in DVDs or flash drives or whatever media you like, and you can charge nominal amounts for the media. I.e., you don't have to make it easy to get the sources. And you don't have to provide the built product for free.
You can do a lot within the boundaries of the GPL. If IBM/RH does that, so what?
One can even do this sort of thing w/o GPL. For example, SQLite3 is in the public domain, yet the SQLite Consortium exists and makes what I imagine is good money for D. R. Hipp and his employees with zero competition from forks precisely because SQLite3 is very difficult to credibly fork, and SQLite3 is difficult to fork because the better test suite for it is proprietary and secret.
To a business, open source is a tool. Even for individuals, open source is a tool. A young person just starting out and with few resources might make useful software open source so as to gain notoriety and better employment, or even to start a business.