Looks like you're basically right. It's much better than smoking, but not as good as fresh air. Quick summary:

Inflammatory Pathways: A 2024 study in the American Journal of Physiology found that regulated cannabis aerosol still induces transcriptomic and metabolomic changes in lung cells. It specifically affects lipid biosynthesis and oxidative stress responses, which are involved in lung repair and function.

Reduced Burden vs. Smoking: Recent human studies (e.g., UC Davis, 2025) indicate that the inflammatory markers in the breath of vapers are significantly lower than those of tobacco or marijuana smokers. Vaping appears to sit in a "middle ground"—cleaner than smoke, but more reactive than non-use.

Fine Particulates: Regulated vapes still produce PM2.5 (ultrafine particulate matter) that can penetrate deep into lung tissue, potentially triggering cardiovascular or respiratory irritation over time.