Most of the issues are just stemming from its centralized nature. Typo squatting for example and other security issues. Beyond that the whole ecosystem around npm is just so bloated. The amount of data you have to pull for any tiny project is ridiculous.

Granted some of those issues is just down to growth of the ecosystem, so it could happen to deno as well. But my hope is that deno community will not repeat most of past mistakes. And it's decentralized nature will help with that.

Npm is great, but it's not ideal to structurally depend on a centralized service for normal functioning.