You don't, though a MS may be borderline necessary. Without a PhD you will likely only lose out on some jobs at companies that are doing hardcore ML research or

You don't, though a MS may be borderline necessary. Without a PhD you will likely only lose out on some jobs at companies that are doing hardcore ML research or are simply more invested in the DS hype than actually looking to solve problems with DS. There are plenty of companies out there with data science needs that can be filled by non-PhD data scientists.