No idea about all the behind the scenes stuff at the Texas Observer, but I do know that supporting a legacy liberal publication costs about as much as one quickly forgotten ad buy in a mid-tier Senate race and yet...
To the extent that anyone with money throws it at "media," rich donors like shiny new things which they usually quickly forget about, and hate anything with any tiny chance of being effective because they can't 100% control the message.
One rich guy, dubbed "The Real Thing" by one substacker, did throw a lot of money at some media outlets recently. His name was Sam Bankman-Fried.