There no reason today why SSO, even basic Azure AD and Google ID only shouldn’t be a standard for a paid B2B product.

It’s a red flag for me and usually indicates that the company isn’t confident in the value they offer for their higher tiers, or they can’t afford what they offer without soaking big institutional customers. You’re exposing my company to elevated risk. Most people pay, but that’s on my buyer’s checklist and we reject a dozen or so of these request every year.

My favorite was AirTable. It’s more expensive than O365 E5 at retail. Gave me a good laugh.

I agree with you about tier pricing and as I mentioned it's considered controversial...but as https://sso.tax showcases in their extensive examples, the large enterprises that control that market have increased their prices considerably, and some by 6300% at the far spectrum.