Those projects were a bizarre affair. There was I think Maemo, Moblin, LImo, SLP, Bada, Leste, MeeGo, Mer, Tizen, Sailfish, Nemo... all forks, merges, reforks of the same thing. They seemed to spend all their time and energy continually rebranding, forming and disbanding consortiums, creating new websites and logos. They never just got on with it. Ridiculous wasted effort when the market was possibly still just about open to them.
It's essentially a perfect description of a clash between a rather hardcore technical community with some academic/student background and a typical Korean Corporate conglomerate, with the expected end result.
You seem to be talking from a position of ignorance at least when it comes to Jolla and Sailfish OS. The former is probably the best non-mainstream mobile OS that can be used today.
> The OS is an evolved continuation of the Linux MeeGo OS previously developed by alliance of Nokia and Intel which itself relies on combined Maemo and Moblin.
Sailfish's market share is so low it doesn't seem to be measurable.
When these projects were at their peak there was just about a way for them into the market. There isn't now. If they spent their time working on just one branding of these projects instead of creating yet another new name, website, and icon they might have gotten somewhere.
the native apps were so fast, everything happened instantly. Also the UI looked gorgeous. In contrast my current oneplus 8 pro feels like a complete regression on the software side.
Technically even WebOS was open-sourced and still around as LuneOS, but its last update was Halloween 2019, so it's likely defunct.