I disagree. My phone supports UVC video input so I can plug my $25 standards compliant borescope into it, I can plug my standards compliant rme sound card into it for field recordings, and I have a bunch of input peripherals that just 'surprise work' with android now too.

You should have a look at the GATT spec for bluetooth LE and the UART service. It has never been easier to build scientific devices that rely on your phone for compute. The thing is, I think we're actually at the point where it's cheaper/ more reliable/more predictable to stick an nrf52 chip into a peripheral than try to support a physical connection to your phone - I guess from a security standpoint as much as anything else.

There are a _ton_ of scopes and stuff that sit in the prosumer space that leverage your phone. They're just not wired, and I think it makes sense for them not to be.