For me, FPU emulation is a must. However I'd temper that by saying just the 040 FPU subset, which includes one or two operations missing on the 060fpu and be able to trap properly any missing ones so that a software solution is possible (ala oxypatcher).
To be fair, if the CPU core advertised itself as a basic 020 but silently supported the 040fpu and some other 040+ instructions like move16, lots of software would just work.