As far as I know, USA is already a long time leading the number of Bitcoin ATMs. It may be many developers focus on improving the number of Bitcoin ATMs there, considering it will be more useful to spread in USA and it is legal already. While in the other countries, the Bitcoin ATMs are probably still useless. One of the reasons, in some countries, Bitcoin cannot be used as a payment tool, just a digital asset. If people only use for a digital asset, it is not urgent to have Bitcoin ATMs.