This is, fundamentally, a gross misunderstanding or misrepresentation of the way that open source works in general, and of the way Red Hat-employed developers in particular interacted with the ecosystem.
I was in the engineering side in various positions for nearly a decade. The policy was upstream first. Open source first. If you think that the engineers at Red Hat didn't care about open source, or that anyone WANTED to invest god knows how many man hours into trying to create a sane experience from scratch, you're badly mistaken.
Pulse was optional in gnome-settings-dameon for a long time, and the primary reason it's deeply integrated now is because people LIKED IT (the horror!), since it finally solved a bunch of problems with Linux audio, and the dbus backend made stuff like "media keys work out of the box" seamless.
Similarly, GNOME has a dominant place in the market because... people liked it. It's market competition. GNOME had/has a place in Red Hat as the de-facto user experience for Fedora, and Fedora's principal role is user experience testing/feedback for the next version of RHEL, at all levels of the system, but the number of users who are gonna run Fedora without a shell is low.
Principally, a lot of Red Hat's engineers ran (and probably run) Fedora as a development workstation, though there was a fair amount of Gentoo, Arch, Slack, and others.
The only reason why there's a perception that "non-Red Hat stakeholders didn't matter" is because the vast majority of community users weren't submitting patches, and the other big vendors (SuSE, Canonical) were working on other DEs (KDE, Unity) which only shared parts. EndlessOS and other projects were GNOME because... it worked.
Pulse and systemd came into being because better solutions did not, despite a bunch of effort. I've used Linux since the 90s. ALSA was better than OSS, but it had enough thorny edges that JACK still had to be a thing (and still is, for audio engineering). Pipewire is an iterative improvement on Pulse. Audio will never be done.
OpenRC, Upstart, sysvinit, runit, and others were all terrible in various ways. The sheer existence of stuff like supervisord speaks to the existence of that. If I'm going to bet, it's always safe that whatever "booo systemd" person I'm speaking with has never actually had to maintain, troubleshoot, add features to, or otherwise work with pre-systemd init systems in any meaningful way.
Red Hat's business is consulting (or at least that's what "platform" is, discounting OpenShift, but "platform" had been stagnant in revenue for a bit, which precipitated the buyout). It is not selling Linux. It is getting paid to help companies make Linux work for them so they can save money in other places.
It is in writing features which make Linux better because some customer needs/wants it and has a bag of money, but not the in-house expertise to write it.
It is not desktop Linux, and it hasn't been since RHEL3 (or maybe before that). Any argument predicated on that is built on quicksand. Don't make a Texas sharpshooter fallacy.
You have (had) a bunch of very smart people who were very passionate about open source working in Linux every day, at a company with an "upstream-first" policy. They were actively working with/against desktop Linux user experience at airports, at home, on newer laptops, trying to get on Bluejeans calls, etc. It should not be surprising that they also saw problems and wrote solutions, which the gratis marketplace liked enough that they have widespread adoption.
You can personally dislike those technologies, but condemning their existence is just a different way of saying "I don't like open source when ideas I don't like succeed".
