[davb]

I don't agree. There's a lot wrong with the marketing copy of the website but I think that statement is quite clear.

For most countries where SIMs are commonly in use (i.e. not the US where CDMA is still a thing and not all consumers are comfortable with GSM), people generally understand that to change SIM you need an unlocked phone. I think the question is intended to answer whether you need a phone on a specific GSM or UMTS band, which you don't.