I’m no expert in the subject but I think you’re way, way out of date, at least as far as audio is concerned. What you’re stating was readily available 30 years ago. DSPs, were invented in the ‘70s and were pretty advanced by the 90’s. Motorola and others were making digital signal processing chips but I recall back in the mid 90’s when SHARC processors became the “flavour of the day”. Quite a few bits of digital studio gear around that time were advertising they used SHARC chips, which natively calculated filters (and other DSP tasks) in 40bit float and did it extremely quickly/efficiently because the actual chip instruction sets were built for real time signal processing applications, they could then internally convert their output to all the standard fixed point bit depths (up to 24bit) as well as 32bit float. The top of the range SHARC chip was like $8 or something but I haven’t heard of them for years, not sure they still make them.Taking a binary fixed point A/D sample and turning it into a binary floating point representation is a simple format change that only involves bit shifting to form the mantissa, and an according adjustment of the exponent. That's a different ball-game from actually doing real-time filter calculations in 32bit float, but it could well be that for the latter the required float processors for use in consumer portable equipment are now available.
As far as I’m aware, floating point calculations for filters, etc., in AD converters has been standard for at least 25 years, even in cheap converters.
G