Why would anyone use this over Proton Mail or the gazillion alternatives if it treats people like shit.
The software is the "primary component" but a service is far more than just a piece of software.
It's providing infrastructure for the software to run in, maintaining said infrastructure, providing support to customers, billing/accounting, hiring people to do all of that etc. I'd even go as far as saying that the software being hosted ifself plays no major role in the service part.