The PL as a brand already has a massive audience, it's huge enough to make money right away. Of course the infrastructure would cost money, at the end of it it's pretty obvious they'd make a load more than the TV deals get them. There's a reason TV companies are paying so much.
The PL are absolutely loaded, they would not struggle to set this up.
Edit: As for my computer and business literacy, I've been working in software for over 12 years, I'm aware of the enormous undertaking to be able to maintain a streaming platform at the size that would be needed but just because it would be hard and costly doesn't mean it's not worth doing, it would end up in a massively improved product for the fans and thus attract more customers. It's a massive no-brainer.