In the case of no/low-code tools, Budibase[1] offers SSO on its open source edition, which makes it easier for me to adopt it and gain confidence in the product before committing to an enterprise plan with obscure prices and shady sales techniques.
But it's a shame, since the competitors in this space are awesome (ToolJet, AppSmith, NocoDB, Baserow, etc) but rarely consider SSO as a simple and basic feature. They usually put SSO as an enterprise feature in the highest price tier possible.
Btw, Grist[2] is another honorable mention in this space with open source support for SSO.