It is partially open-source, as I understand it, the core OS is, but some UI components on top etc. are still closed source.

https://docs.sailfishos.org/Services/Development/Sailfish_OS_Source/

Jolla and SailfishOS inbound

It seems that the settlers were shooting at the Palestinians, after wrestling the gun from them and shooting them back, THEN the Israeli soldiers responded back, killing the villagers.

Also unsure about that, but it is true that Google help fund its development (unless they stopped?), and I would also believe it its just to help themselves.

What would actually make it succeed though? I have been using it for a long time, not like there are any issues.

Just seems more of a culture for people just use Chrome. Is marketing the solution or what?