SSO shouldn't be a manual setup, as many SaaS products offer self service SAML or OIDC configuration. I heard the SSO tax is often used as a filter for larger companies that will drag you through lengthy security assessments as part of their vendor process. That makes sense, however, these days, SSO is hardly limited to larger organizations.
I see you offer Google sign-in at the lower tier, and the same workaround could be available for Microsoft. If you offered sign in with Microsoft, I can use my Okta SSO, without your involvement, because it is already configured within my Microsoft organization. I would imagine Google + Microsoft would cover the vast majority of organizations.
https://learn.microsoft.com/en-us/azure/active-directory/dev...
BUT as a 2x SAAS business I found that this absolutely worked. Make them call. I hate that it works. I have tried irrationally hard to make transparent pricing work for larger customers, and failed. I don't think it's a law of nature, and in some cases it can work. But generally, talk to larger customers.
I think SSO (particularly something like Okta) means they will be a client with whom calling and talking to will be a net positive for you and the business. This is basically the single most obvious feature to segment off.
I think some managers like the process. It's a good excuse to kill 1-4 hours emailing back and forth, scheduling calls, having calls, et c. Low-stress, even enjoyable, still counts as Real Work. Gives you something to brag about when angling for raises or promotions, or when interviewing, if you get a discount (even if ~everyone gets the same "discount"). Plus I think some of them just aren't comfortable signing up for something for business purposes when they haven't spoken with a real person on the other end. Gives them some kind of reassurance or confidence.