Has anyone tested requiring a credit card for free trials vs. completely open access?

We spent months debating whether to ask for credit card info upfront. When we finally removed the card requirement, our trial sign-ups shot up by 300%, but activated users barely changed.

It turns out lower friction just filled our pipeline with ghost users who never actually set up their account. Adding a bit of friction back actually improved lead quality and reduced support load.

Have you noticed better long term retention with high friction or low-friction onboarding?