I'm afraid I can't agree. It will help facilitate that adoption by giving people (including people outside the cryptosphere) something to download that is easier to use. Without that such efforts face a very uphill battle. You could possibly reach beyond the cryptposhere to other sys admis, software developers, etc. who are comfortable with command line tool, but that's a narrow market with little obvious attraction to alternative monetary systems.
I think we disagree on what Monero is in scope. I see it as a protocol for third parties to leverage and use in their products and services, and not (ultimately) as something the end user will ever need to download and run independently. Hardware and software wallets will be third party tools of various flavors depending on the needs of the user, but none of which require the user to download core Monero binaries to use.
It will help facilitate that adoption by giving people (including people outside the cryptosphere) something to download that is easier to use.
I'm saying that people have no reason to download and use the core software unless it's part of a product or service that gives them a good reason to use it.
EDIT: for example, Poloniex doesn't need an XMR GUI to offer users a robust and intuitive crypto exchange... and XMR.TO and Shapeshift don't need an XMR GUI to offer users quick and easy btc conversion. MyMonero doesn't require a bundled GUI to offer its own simple web wallet service.
It's services like those that ultimately attract users, not core implementations that end-users will never bother with anyway