Apple's stuff is probably orders of magnitude more reliable, the system they use has been battle-tested for decades.
Both Starlink's sat-cells and Apple's Globalstar link will be a real benefit for people who get stuck in a bad situation unprepared, but if I were a serious rock climber or similar, I'd still prefer a full-scale Globalstar, Iridium terminal or EPIRB device, then an iPhone with Globalstar, and only then Starlink's offer.
Globalstar with an iPhone is not battletested at all. A huge chunk of the complexity of a sat system is in the ground side and the iPhone form factor is new.
Both Starlink's sat-cells and Apple's Globalstar link will be a real benefit for people who get stuck in a bad situation unprepared, but if I were a serious rock climber or similar, I'd still prefer a full-scale Globalstar, Iridium terminal or EPIRB device, then an iPhone with Globalstar, and only then Starlink's offer.