“Have onboarding questions, then a generic paywall, then more questions related to specific premium features, or even have users set up those premium features, then have a feature paywall and say these are part of the Premium plan. If they don't get it you explain to them everything they're going to lose.”

Loss aversion: let users configure premium features before showing the paywall

Users invest effort building out a premium setup during onboarding, then hit a paywall that explicitly threatens to wipe what they just configured. The sunk-cost feeling does the persuasion that the first generic paywall couldn't. The second 'lose everything you set up' paywall is what actually converts the holdouts.