For Apple to develop an ISA they would have to develop a CPU. Something they don't do inhouse.
Up until now the CPUs have been designed by ARM. Cores like Swift for example were not developed at Apple, but rather at ARM.
The likelihood of ARM releasing a chip into the wild with a non-ARM ISA is not all that great, since the ARM ISA is what ARM makes all of its living from.
Until the day where Apple is capable of creating a CPU by themselves there will be no Apple ISA.
Up until now the CPUs have been designed by ARM. Cores like Swift for example were not developed at Apple, but rather at ARM.
The likelihood of ARM releasing a chip into the wild with a non-ARM ISA is not all that great, since the ARM ISA is what ARM makes all of its living from.
Until the day where Apple is capable of creating a CPU by themselves there will be no Apple ISA.