Is Iridium really competitive for business jets? The bandwidth of even their next-generation satellites does not seem competitive with the GEOs, and I'd guess bizjets should be mostly fine with their latitude limitations.
I'd expect most of them to go with one of the Ka band these days; they have pretty small antennas available these days as far as I know.
a small to medium sized business jet can easily mount an iridium terminal on top of it, where even the smallest/least capable geostationary vsat cannot.
you can fairly easily integrate iridium into something as small as a cessna 172...
at the minimum iridium will provide the ability to make phone calls to/from the PSTN while in the middle of an ocean on its smallest terminal. go up in terminal size a bit and you get something good for 500kbps of data.
for very large business jets that would be crossing the atlantic or pacific, that's a different market (overlaps somewhat with the same aviation VSAT terminals you would see on a 737-900 MAX)
I'd expect most of them to go with one of the Ka band these days; they have pretty small antennas available these days as far as I know.