Both are credible. The right answer depends on your governance requirements and where your organisation is going, not on a feature comparison table.
This question usually arrives framed as a migration that has already been decided, looking for justification. It is worth taking a step back, because the cost of moving a mature delivery estate is routinely underestimated by a factor of several.
Where Azure DevOps still wins
- Environment approvals, deployment gates and audit trails that map directly onto regulated change processes
- Work item traceability from requirement through commit to release, which auditors ask for by name
- Fine-grained project and repository permissioning in large organisations
- Mature YAML template composition across projects
Where GitHub pulls ahead
- The AI-assisted development ecosystem, which is where Microsoft's investment is visibly going
- A far larger action marketplace and community familiarity — hiring for it is easier
- Tighter integration with the open-source supply chain tooling most teams end up adopting
Our advice
Greenfield, no heavy compliance burden: start on GitHub. Existing estate with working governance and no specific pain: stay, and revisit annually. Both are supported and neither is going away, so a migration should be justified by a concrete problem rather than a roadmap slide.
If you do move, move one low-risk repository first and run both in parallel long enough to learn what your pipelines actually depend on. There is always something.