There are certainly such allegations about a "shortage" here in the USA but I'm not sure what segment of corporate flying is affected. We have individual-owner Part 91, corporate-owner Part 91, Part 135 charter and fractional Part 91K. The airline hiring would appear to be drawing at least some pilots from the corporate world. How many ? Dunno...
I don't know enough about this area of aviation to comment. Maybe someone who does know will comment.
https://www.flyingmag.com/pilot-shor...iness-aviation