Hi Darryl,
Clearly this is a valid concern. I also don't like being tied to an Internet connection all the time. For example, I like having browser access to e-mail (so I can check up on things when I'm away from my own machine), but I would never trade the cached off-line access, load speed, search speed, backup and other features that I get with Outlook.
However, I don't think you should constrain the notion of web-based technologies to a live internet connection. Web servers are easily run on local machines now (IISExpress, paster, etc), and fully functional html rendering controls are easily hosted in other applications (VS itself uses some html-based windows). Web-based also doesn't mean that the data needs to be stored somewhere in the cloud. For example, http://www.ormsolutions.com/tools/orm.aspx (with no query string) tries to open a local file (assuming an HTML5-compliant browser that supports opening local files). If you have a local web server running, you can grab the local source for this page, save it as an .htm file, grab the three referenced javascript files, and have a local orm file viewer running in your browser with no internet connection in a matter of minutes.
A big part of the issue with modeling is that many of the participants in the modeling process--both modeling experts and domain experts--are not developers, so requiring a heavy-weight development tool to create, view, discuss, and share models with all participants in the process can be a major stumbling block. Microsoft effectively killed the Visio-based ORM tools by packaging them in high-end, developer-targeted Visual Studio box. Simply put, we need to make it easier to use ORM models across a wider audience.
Of course, the broader availability of ORM is also the gist of your original query. I fully agree that we need broader access, and that developers and development tools are a big part of it. However, I also think that focusing too much on the back end technologies obscures the vision of where we want to be. The goal is to be able to design, implement, and execute at the conceptual level, with the backend becoming less and less of a concern over time. I think web-based technologies offer ways to approach this problem in a way that local apps and development tools can't touch. I'm not sure I would have said that five years ago, but the world is changing both in terms of connectivity and in the client-side browser capabilities.
-Matt