Most applications do not exceed 24 bits of precision so 32bit float does not degrade quality with 24bit mantissa.
Some applications can use 64-bit float precision like the historical Csound.
Furthermore, several modern A/D D/A converters support a 32bit INTEGER resolution (in addition to DSD), in particular the AKM AK557x and AK449x converters.
It may be useful to read an article by the founder of Mytek that explains the reasons to go beyond the 24 bit PCM: https://mytekdigital.com/download_library/Beyond_24_bit_Michal_Jurewicz_Resolution_2014.pdf
There are probably few applications that support 64-bit double precision. What is JackAudio/Ardour intentions about it?
An intermediate transport-only measure could also be using 32bit integer instead of 32bit float and perhaps it is already applicable as an experimental configuration of JackAudio/Ardour?