They're going to lose the people like me anyway when phones can send a SOS by satellite, so their revenue from me will either go to $0 and I'll sell my InReach on eBay, or they can get some small amount of revenue (enough to cover the administrative costs of registering the device) from me.
Good point – now that the iPhone has satellite SOS, the market has changed, and the pure SOS use case has become a lot less compelling.
Some users still prefer a standalone device, want P2P messaging functionality (until Apple adds that, too), or need coverage beyond Globalstar – I'd be curious to see how much of the market that is, in the end.