This has not been the case for most commercial software for the past 20 years, during the cloud era. If you could steal a dump of random Facebook source code, it would be 99% useless because it’s so closely tied to the infrastructure. There’s almost nothing you could usefully run on your own PC or server VM.
But these ML models are like neutron stars of computation density. You can’t really peek inside to see what’s going on either. An unknown stolen model’s properties would need to be discovered by experimentation.