I haven't really touched Lightsail in years, but this page shows a really nice graph that helps you understand your instance's CPU usage: https://lightsail.aws.amazon.com/ls/docs/en_us/articles/amaz...

From what I've seen of benchmarks online, DO's droplets have better sustained (and often overall) performance than Lightsail, and this looks to be the reason why.

(Which isn't to say people should avoid Lightsail, but I don't think Lightsail is the obvious 1:1 replacement for DO that a couple of people in this thread want it to be. Lightsail intentionally restricts various things to avoid cannibalizing their normal AWS sales.)