It did "math out" because these industries heavily lobbied and regulated that starting an alternative is close to impossible. Think about Wise: How many companies out there have the same service? The closest are Revolut and Airwallex. So in a world of 8 billion people and millions of businesses, there are only 3 companies that do the same thing that Wise do. In comparison, there are thousands of banks around the world.
Wise's USP is a consequence of the way the US banking industry works (possibly as a result of US regulation). Free and instantaneous interbank transfers are ubiquitous in other banking systems, as are low-fee international transfers.
Wise is a British company with lots of customers around the world, the article is by someone in New Zealand.
It is cheaper than British banks for international transfers. Its business accounts are both easier to open and cheaper to run than those of the banks.
You are right that transfers from personal bank accounts in the UK are usually free and rapid (usually immediate, guaranteed to be within two hours), and similar or better in many other places, but Wise still has an offering beyond that.
