Cypress's UI is genuinely good for exploration, but I'd push back on the debugging claim. Once you get past the initial friction, Playwright's trace viewer is way more useful than Cypress's failure screenshots. You get the DOM at each step, network logs, console output all together.
The real problem is neither ships with great defaults for writing tests. Cypress's record mode is nice but breeds brittle selectors. Playwright requires you to actually think about your test structure from day one, which sucks at first but saves time later.
The headed mode complaint is fair though. They could ship better debug UX out of the box.