The risk of a mishap is greatest on takeoff and landing. Inflight mishaps are extremely rare.

A “flight” is one takeoff and one landing. The largest aircraft have the longest duration flights. They might be airborne 12+ hours at a time. They might fly fewer than 10 flights a week.

Small commercial aircraft flying local and regional routes might be shorter than an hour. These aircraft might have 70 flights a week.

A student pilot in the smallest, single-engine GA aircraft might spend all day shooting touch-and-goes to build time and experience. Each touch-and-go is a landing-and-takeoff. These aircraft might have 300 “flights” a week.

Yes, the smallest aircraft are going to have the highest per-airframe mishap rate, simply because they experience the most risky phases of flights much more frequently than large aircraft.

Per-flight, the risks aren’t significantly different.