Language barriers aren't relevant when the country you're outsourcing to has the same primary language. TZ differences are a non-issue for distributed companies already using JIRA and Slack for everything. Those two things would only even be a concern for the tiniest minority of companies.

I'm a software engineer based in Brisbane, Australia, I've worked for two US-based startups who were specifically growing their offices in Australia because it's cheaper to hire for the same roles here than in the US.