Its OK for the line to be muddy. Make sure you have a good working relation with your sales ops counterpart.
Usually sales ops and enablement are slightly different functions. sales ops has also revenue ops elements in it around contracting and quoting for example. One common metric outright owned by sales enablement is time to productivity. THis comes from good onboarding, based on Sales understanding the market, product, customer, tools, pricing, quotation process, SOW terms etc. Most of that has little to do with PMM and we should be grateful for sales ops' exisitence.
If you find yourself in a situation where there are competing interests, draw an accountability chart. For example, PMM is crealy responsible for creating assets/content acorss the buying journey; sales enablement is clearly responsible for sales process knowledge. Dis/agree with your counterpart and align hierarchies around the RACI.