Story

>Seems like there must be more to the story. For example the autonomous operation is only "theoretical"?

One only has to look at some of the U.S. smaller market low-power tv signals to get an idea of what can go wrong. Some are really messed up, and even some of the better performing ones occasionally go down after a power outage or other disturbance and don't come back up unless someone calls the parent station to tell them to check it. Many operators can't see the output of their own transmitters and really don't know what is going on.
Many of the analog stations were rebroadcasting noisy signals from other other low-power stations or misaimed dishes. Some have undetected configuration problems like out of phase audio. (signal produced sound on a stereo tv, but it cancelled out on a mono set) If there is some overlap of coverage of low-power stations, there may still be some audience responses from an area with a sick site. I've seen one station that NEVER has had any audio, and the operator didn't fix it even after being told about it.

Simple things, like a strong wind gust (or sandstorm?) might knock the satellite dish out of alignment. A dish that's close-enough when set up in good weather might not always give adequate signal under other atmospheric conditions. High operating temperatures might contribute to r.f amp failure, or maybe the oscillator going out of lock. Maybe the box isn't quite weather-tight and some moisture gets in contributing to currents between circuit traces, or corrosion.
Old-school equipment would have used a crystal to set the desired transmit channel, but it's more likely there is a digital synthesizer (similar to what's in modern FM tuners) that makes it easy to change frequencies. While the added complexity adds flexibility, it also adds more failure modes. Who knows, a stray cosmic ray might cause the digital section to freeze up. A problem that could be cleared by a simple reset/reboot might persist if there's no one around to do it. If the solar power and battery voltage drops too low, will the equipment always go back to a controlled stable state after experiencing slow transitions through a below normal supply voltage range? Of course these sorts of potential problems apply to the satellite receiver too.

If the transmitter has a display, it's probably a design with a cpu in control of the frequency synthesizer, trim of output power, and monitoring of things like reflected power (an indication of how well the antenna is adjusted to transfer energy from the transmitter). Having a cpu generally lowers reliability, but a custom design might be set up to do intelligent things like adjust the operating hours and power level to make best use of the available power supply ability. I doubt that any custom development is being done.