I won't allow you to incite a conflict with the .io domain holders especially her eon bitcointalk as i don't want to create war on here. The response below should address your inquiry :-)

Tech and SaaS startups often opt for .io domain names because they align with the input/output terminology, offering a concise and meaningful word that resonates with their target audience and the startup community. Additionally, the availability of .com domains for their second-level domains might be limited, further establishing .io as an ideal alternative domain choice. :-)