Different companies will define product marketing and sales ops / sales enablement in different ways. The distinction tends to run along a spectrum where on the one hand, Product Marketing will lead the creation of content that focuses on market positioning and differentiation, and on the other hand, Sales Ops will lead specific activities or content that helps translate that marketing positioning in a way that resonates with the experience of being in sales.
For example, a Product Marketer may create content that talks about how your company has designed product capabilities to addresses a specific pain point compared to other solutions on the market and why that product design provides more value to the customer. From there, Sales Ops / Sales Enablement may package the content into an e-Learning or sales training and also supplement the content with success stories from successful reps and conduct trainings on how tp present the information and handle objections.
Objection handling is an example of where there may be overlap and collaboration between PMM and Sales Ops. In some cases, Sales Ops may start creating the objection handling content but will likely need to circle back to Product Marketing for PMM's perspective on the content to address the objections. In some cases, PMM will start creating the objection handling content but will consult Sales Ops on the most effective way to teach that content to sales.