I'm mid level in private equity and have to travel a lot. I was previously a junior investment banker
The distinction between business and economy is more normally based on flight length rather than job title. E.g. everywhere I have worked has been economy for short flight up to 4 or 5 hours and business beyond, regardless of seniority.
However, some places may tweak their travel policy based on seniority, where the threshold for business class kicks in at a shorter point.