The review process is very cumbersome as well, the company I work for wants users using the Home app, but apple requires we create a homekit compliant app to certify the hardware. I don't understand why Apple can't certify the products with their own Home app.
Lastly there is no way to make our hub present itself for remote connections in Homekit, despite Apple requiring us to use chips certified to their standard. The user has to have an ipad or apple tv in the house to act as a gateway. This is a confusing concept to explain to users if they've been using our protocol for the last 2 years and now want to migrate to Homekit.