Ask HN: How important is it to provide on-prem options for enterprise SaaS?

I've been working on a design for a B2B SaaS application, and I'm struggling to find information to help make a decision about building a cloud-only product, or designing for mixed cloud-only and private deployment options.

The option of using managed cloud services (e.g. databases, auth, app platforms, load balancing, etc...) is very attractive, but the concern is leaving large segments of the market on the table due to a lack of private deployment options.

I see major SaaS applications that manage what could be sensitive (business) data which are cloud-only (e.g. Slack), and some that provide private and cloud deployment options (e.g. GitHub). Is there a consensus on this today? What does this decision tree look like?