I was discussing this with Eric Lyon cause we're getting an official fftease 3.0 release out soon (heads up).
It seems that people who need this are the ones who still use some externals that were only compiled for 32 bits. So I guess the question should be "which relevant externals are still only available for 32 bits?"
The new macOS systems are 64 bits only, sooner or later we'll all have to provide 64 bit builds for the relevant externals out there.
I haven't checked them all thoroughly but it seems that all externals from Pd extended are available in deken for 64 bits, right? So I can't see why people still need 32 bit versions. Or I mean I don't know which library is still 32 bits only and I guess what needs to be done is just get them compiled for 64 bits anyway, and I could help with that.
cheers