What's the best mirrorless camera for a beginner on a budget?

Across the reviewers we read, the most-cited affordable full-frame entry points are the Canon EOS RP and the older Sony a7 III. The RP is repeatedly called the smallest, lightest and cheapest way into full-frame, though communities warn it struggles with fast action. The a7 III is praised as a still-excellent all-rounder years after launch. A renewed Sony a7 II is cheaper still, but reviewers flag its dated autofocus and poor battery life.