I believe that it would be possible to make it into a website, yes.

The main reason why I haven't gone this way is because of the trust issue, which most users care about. At the moment, user data flows only between the Google servers and the user's local computer, which is easy to check. With the website, it's harder for the user to know that the Unattach server doesn't store private data.

In addition, it's more complicated for a web application to store data to the local filesystem.