I think there are basically 2 groups: (we need line breaks @unwriter :)
1️⃣ Existing businesses that can cut costs dramatically by utilizing bitcoins ability to enable secure transactions for fractions of a cent. So, if we look at the companies with the largest annual revenue in general and find those who can make the largest profit from saving something like 99% on transaction costs - as long as BSV can deliver on scaling promises - those companies will generate the most annual revenue by using BSV. I don't know the exact numbers but I'd assume it to be industries primarily involved with financial transactions i.e. Banking, Trading etc.
2️⃣ New business models that can monetize Bitcoins ability for secure micropayments. For the first time, micropayments enable a "charge as you comsume-model" for all products and services that can be tracked digitally. So the success depends on the potential market size for the "prepaid"-model over the "flatrate"-model. If we can put a number on the percentage of users who prefer pay-to-use over flatrate consumption, we can approximate the revenue potential of BSV-based businesses by looking at existing companies. If 10% of netflix customers prefer pay-to-use, a competitor could gain 10% of their market cap. If its larger than 50% it gets interesting. ;) And of industries using new tech AI, IOT, AR to throw a few buzzwords into the mix.