I am working on Stripe Tax, but do not know Lemon Squeezy so well yet. But something Lemon Squeezy does different are the following: the KYC works different and is more restrictive. One of the differences to Stripe considering we still give you as a merchant the responsibility to be tax-compliant after all (you need to add tax registrations into stripe explicitly). Also think about maybe fraudulent cases, LS must be much more restrictive otherwise their payment provider is blocking them.

One thing which is weird about tax is physical presences in some cases. In some countries, you actually might need a representative to file your taxes. Plus you need to learn how to register in those countries and how to file taxes.

There are probably more things that you need to look up, but that’s what I remember.

Stripe itself, is an abstraction layer onto of payment network and banking APIs.

What's the barrier to entry for starting up a similar business?

> What’s the barrier to entry for starting up a similar business?

The merchant of record model.