Has any competitor copied anything from Deno?

I don't think I'd go as far as "copying" but Deno was the first to aggressively push for web standards in server-side runtimes and certainly helped accelerate getting them adopted in that environment.

I work at Cloudflare on Workers (but infrequently work on our runtime) and I've always been pretty impressed with Deno. Their recent-ish support for built-in OpenTelemetry is something we've been wanting to do for a while and have been working on, but Deno was able to build a good implementation of that in that time.

Deno basically popularized the idea of a standalone JS runtime that primarily relies on standard Web APIs over "in-house" APIs like Node, although we can say that those standard APIs didn't exist yet when Node was created and for most of its rising period.

I think it’s fair to say that work on the experimental-strip-types option in Node was inspired/energized by a desire to try to catch up with the DX improvements found in Deno for Typescript-first development that is now the norm.

I always thought Deno was more or less trying to copy the Cloudflare (edge) runtime, but decided incompatibility was a good idea. The ecosystem bifurcation was the mistake, which they came around on, but it was already too late by then.