The meaningful question isn't in observing the issue, but in what happens after. Chaos engineering is about making sure you still have enough of a chance of success in the face of failures. For CI, success means an error report that correctly captures whether the PR in question is breaking anything (... at least, anything we're testing). If your process means you can be sloppy about isolation and still get that, then I'd be okay with calling that an example of "chaos engineering". If being sloppy about isolation means you have failing tests in many CI runs that have nothing to do with the changes under consideration, that's not "chaos engineering" - it's just bad CI.