Heck, I work at a 20 person company and this is still generally true. No one is stopping me from using a new service, but using AWS means no new paperwork and no questions.

Actionable advice on this would be: If you're B2B, have an option for yearly billing via invoice.

Billing yearly via invoice vs a monthly direct debit means our finance people deal with payment, and just ask Engineering once a year if they should pay this weird bill they got. Billing via direct debit means I have to do paperwork every month. I don't enjoy things like paperwork. I do enjoy things like building a single customer MVP version of your service on AWS in a couple hours. You can guess which I'm going to choose if you don't offer yearly billing.