Snowflake has stated that they are committed to making Snowflake Native Apps available on all major cloud platforms. They have also stated that they are working with GCP and Azure to make this happen as soon as possible.
In the meantime, developers can still use the Snowflake Native App Framework to build and deploy Snowflake Native Apps on AWS. They can also use the Snowflake Native App Framework to build Snowflake Native Apps that can be deployed on GCP or Azure once they are released.
If you are interested in using Snowflake Native Apps on GCP or Azure, I recommend that you sign up for the Snowflake Native App Framework private preview. This will give you early access to Snowflake Native Apps on these platforms, and it will also give you the opportunity to provide feedback to Snowflake.