Slight clarification here. Might not apply in OpenObservability's case but might help others on their journey to enterprise sales with their projects.
Those are typically conversations with managers holding $X purchasing authority, typically like $500K for a US director'ish level, within multi-billion dollar companies. These managers usually aren't averse to spending on open source projects. They're averse to cutting a check not tied to a support contract with responsive, polite, helpful support with published support policies at 0300h local time on a break-fix line with 75 other people from other support teams in the company watching. A surprising number of open source projects won't offer that guarantee, and instead only offer the option to "donate" with vague promises of priority support. More projects are getting better at this more recently, but it takes a surprising amount of red tape to onboard as a vendor into these organizations, and a lot of open source teams don't have the appetite for putting up with that.
Until kind of recently, the conversation switching to the SSO Tax is really about accessing that level of guaranteed support delivery.