Maybe... it depends on the amount of _trust_ that you put in the remote domain. My prediction is that the Deno ecosystem will aggregate around a few, large repositories that will have good guarantees araound immutability and good track records to addressing vulnerabilities.
For large projects like React, lodash, eslint whatever, I expect some of them will start hosting their libraries on their own networks, like it used to be when Javascript was only frontend and you would have a script tag importing jQuery directly from jQuery's CDN. The reason it worked was because jQuery was sidely known and trusted.
